There is absolutely one thing that every vintage car owner has in common: The hardships of diagnosing car troubles, especially OBD1 diagnostic trouble codes. And the differences in the OBD1 code lists and other parts make it even harder.
There are maybe a few of the questions that may be running through your head when your car starts acting up.
- “How do I find out what is wrong with my car?”
- “What are OBD1 codes?”
- “Do I need a mechanic
- “Are the OBD1 diagnostic trouble codes universal or manufacturer specific?”
- “What does this OBD1 code mean?”
Do not worry!! In this article, you will understand what are the differences and get some lists of OBD1 code from different brands with meaning/fault locations.
Contents
- 1 What Are OBD1 Codes?
- 2 The Difference Between Each Brand And Model
- 3 OBD1 Code Lists
- 3.1 GM OBD1 Diagnostic Code
- 3.2 Ford OBD1 Diagnostic Code
- 3.3 Acura & Honda OBD1 Diagnostic Code
- 3.4 BMW OBD1 Diagnostic Code
- 3.5 Audi OBD1 Diagnostic Code
- 3.6 Nissan OBD1 Diagnostic Code
- 3.7 Lexus OBD1 Diagnostic Code
- 3.8 Subaru OBD1 Diagnostic Code
- 3.9 Mazda OBD1 Diagnostic Code
- 3.10 Toyota OBD1 Diagnostic Code
- 3.11 Jeep OBD1 Diagnostic Code
- 3.12 Dodge OBD1 Diagnostic Code
- 3.13 Chrysler OBD1 Diagnostic Code
- 3.14 Saturn OBD1 Diagnostic Code
- 4 Final Thoughts
- 5 FAQs
What Are OBD1 Codes?
OBD is short for On-Board Diagnostics, an automobile term used to refer to a computer that monitors your engine through a series of sensors in order to track and regulate the performance of your car.
OBD1, also referred to as California Standard, is one of the first versions of an On-board diagnostic system in any vehicle. It is manufacturer-specific, meaning that every car brand has its own particular scanner that isn’t interchangeable with other brands. The driver will receive the system’s warning via the “check engine” light or MIL (Malfunction Indicator Light). OBD1 codes are a list of trouble codes associated with the on-board diagnostic standard (OBD1) implemented in vehicles made for California from 1991 up to 1995 to control the region’s emissions. People can use an OBD1 scanner to read and clear the fault codes. It will connect to the system to identify the problem, show OBD1 diagnostic codes (DTC, for short), and pinpointing the problem on its screen.
The Difference Between Each Brand And Model
OBD1 is also not standardized, meaning that the location, connector, or the trouble code in each brand will differ from others with the same problem. This article will take General Motor (GM) and Ford to make comparisons:
The Difference In Location Of OBD1 Connectors
The diagnostic connectors that allow communication between the OBD system and the OBD1 scan tool are also located in different locations.
For example, for General Motors (GM) vehicles made before 1995, the connector is located under the driver’s side’s dash panel. It may be covered by a black plastic cover, so you should pay attention to look under it. For Ford vehicles, the connector is located in the engine compartment by the fender near the battery.
The Difference In The Design Of The OBD1 Connectors
The connectors look different too, below are images of both for easier identification and differentiation. The one used by General Motors has 12 pins. Even though the design varies from manufacturer to manufacturer, the standard pins like the power, ground, and diagnostic pin may be the same in most car brands.
The Difference In The OBD1 Codes
While diagnosing the car problems, you can notice several OBD1 codes as flashes on the Check Engine Light. As a result of unstandardized, not only the location and connector but also the OBD1 code lists will be different in each car brand, or even the models. It may be the same number, but the meaning or the fault location will vary depending on the brands or models. For examples, when it comes to Ford, we have two test modes, namely:
- Key On Engine Off (KOEO)
- Key On Engine Running (KOER)
OBD1 Code Lists
As this article has mentioned before, OBD1 is not standardized so the trouble code will vary between all brands. Maybe the same problem but it will have different code meanings or numbers. Here are some lists of OBD1 codes from different brands that may be useful for you.
GM OBD1 Diagnostic Code
| Codes | Meaning/Fault Location |
|---|---|
| 12 | No distributor reference pulse (diagnostic test active) |
| 13 | Oxygen sensor circuit open or no activity |
| Left bank O2 sensor circuit open or no activity | |
| 14 | Engine coolant temp sensor error (high temp indicated) |
| 15 | Engine coolant temp sensor error (low temp indicated) |
| 16 | System voltage too low |
| 17 | Camshaft position sensor error |
| 21 | Throttle Position sensor error (signal high) |
| 22 | Throttle position sensor error (signal low) |
| 23 | Intake air temp sensor error (low temp indicated) |
| 24 | Vehicle speed sensor error (open circuit or no activity) |
| 25 | Intake air temp sensor error (high temp indicated) |
| 26 | Quad Driver Module (QDM A) error |
| 28 | Auto transmission range pressure switch error |
| 31 | Waste gate solenoid circuit error |
| Gear Position Switch (PRNDL) error | |
| 32 | EGR system failure |
| 33 | MAP sensor circuit error (signal high indicating low vacuum) |
| 34 | MAP sensor circuit error (signal low indicating high vacuum) |
| 35 | IAC problem or idle error |
| 36 | MAF sensor error |
| 24x Crankshaft position sensor circuit error | |
| 4T60-E Shifting Error | |
| 37 | TCC brake switch circuit error |
| 38 | TCC brake switch circuit error |
| 39 | Clutch switch circuit error |
| TCC error | |
| 41 | Ignition control error |
| MEM-CAL error | |
| Computer Controlled Ignition Cam Sensor Signal error | |
| 42 | Ignition bypass circuit error |
| 43 | Knock sensor error |
| 44 | Oxygen sensor error (lean condition indicated) |
| Left bank O2 sensor error (lean condition indicated) | |
| 45 | Oxygen sensor error (rich condition indicated) |
| Left bank O2 sensor error (rich condition indicated) | |
| 46 | Pass-Key II (VATS) system error - circuit out of freq range |
| 47 | UART (serial data) circuit error |
| 51 | PROM error |
| Incorrect MEM-CAL | |
| 52 | Fuel cal-pak incorrect or missing |
| 53 | System voltage too high |
| Digital EGR Valve solenoid 1 error | |
| 54 | Fuel pump circuit low voltage |
| Digital EGR Valve solenoid 2 error | |
| 55 | ECM error |
| Digital EGR Valve solenoid 3 error | |
| 56 | Quad Driver Module (QDM B) error |
| 57 | Boost Control error |
| 58 | Trans fluid temp sensor circuit error (low voltage) |
| VATS system error | |
| 59 | Trans fluid temp sensor circuit error (high voltage) |
| 61 | A/C system performance |
| 63 | Right bank O2 sensor circuit error |
| MAP sensor circuit signal voltage high (low vacuum indicated) | |
| 64 | Right bank O2 sensor lean exhaust indicated |
| MAP sensor circuit signal voltage low (high vacuum indicated) | |
| 65 | Right bank O2 sensor rich exhaust indicated |
| 66 | A/C pressure sensor circuit error (low pressure indicated) |
| 67 | A/C pressure sensor circuit error |
| 68 | A/C clutch relay circuit error (shorted to ground) |
| 69 | A/C clutch relay circuit error (open circuit indicated) |
| A/C high pressure switch error | |
| 70 | A/C pressure sensor circuit error (high pressure indicated) |
| 71 | A/C evaporator temp sensor circuit error (low temp indicated) |
| 72 | VSS signal circuit error |
| 73 | A/C evaporator temp sensor circuit error (high temp indicated) |
| 75 | Digital EGR solenoid #1 circuit error |
| 76 | Digital EGR solenoid #2 circuit error |
| 77 | Digital EGR solenoid #3 circuit error |
| 79 | Transmission fluid overtemp |
| 80 | Transmission component slipping |
| 82 | 3x Crankshaft position sensor circuit error |
| 85 | PROM error |
| 86 | A/D error |
| 87 | EEPROM error (flash memory error) |
| 90 | TCC error |
| 93 | Transmission pressure control solenoid circuit error |
| 96 | Transmission system voltage low |
| 98 | Invalid PCM program |
| 99 | Invalid PCM program |
Ford OBD1 Diagnostic Code
| Code | Meaning/Fault location | |
|---|---|---|
| R = Engine running test M = Memory code O = Key on - Engine off test | ||
| 11 | System OK | |
| 12 | Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too low) – ISC | |
| 13 | (O) | ISC did not respond properly (extends to touch throttle then retracts for KOEO) – ISC |
| (R) | Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high) | |
| (M) | ISC sticking, open ITS circuit or TP sticking | |
| 14 | Ignition pickup (PIP) was erratic – Ignition Systems | |
| E4OD Transmission diesel RPM sensor – Diesel RPM sensor | ||
| 15 | (O) | No Keep Alive Memory power to PCM pin 1 or bad PCM (Memory Test Failure) |
| (M) | KAM (pin 1) was interrupted (was battery disconnected?) | |
| 16 | 1 9L & 2 5L – Throttle stop set too high – IDLE or Idle Set Procedures | |
| 2 3L – RPM’s too low – IDLE | ||
| (O) | Electronic ignition – IDM circuit fault – Ignition Systems | |
| 17 | 1 9L & 2 5L – Throttle stop set too low – IDLE | |
| 18 | (R) | Check base timing & advance function – Timing Tests |
| (M) | Ignition TACH signal erratic – Ignition Systems | |
| Spark Angle Word (SAW) circuit failure (1 9L SFI) | ||
| 19 | (O) | No Vehicle Power (pins 37 + 57) or bad PCM VPWR Diagnosis |
| (R) | Erratic idle during test (reset throttle & retest) – Idle Set Procedures | |
| Electronic ignition Cylinder ID sensor/circuit problem – Ignition Systems | ||
| 21 | Engine Coolant Temperature (ECT) sensor out of range – ECT | |
| 22 | MAP (vacuum) or BARO signal out of range – MAP | |
| 23 | Throttle sensor out of range or throttle set too high – TPS | |
| 24 | Intake Air Temperature (IAT) or Vane Air Temperature (VAT) sensor out of range – IAT VAT | |
| 25 | Knock sensor not tested (ignore if not pinging) – KS | |
| 26 | Mass Air Flow (MAF) or Vane Air Flow (VAF) out of range – MAF VAF | |
| Transmission Oil Temperature (TOT) sensor out of range, Transmissions | ||
| 27 | Vehicle Speed Sensor problem – VSS | |
| 28 | Vane Air Temperature (VAT) sensor out of range – VAT | |
| 2 3L w/Electronic Ignition – Cyl ID, IDM low or right coil pack failure – Ignition Systems | ||
| 29 | Vehicle Speed Sensor problem – VSS | |
| 31 | (O,R,M) | EVP – EVP signal is/was out of range – EVP |
| EVR – EVP signal is/was low – EVR | ||
| PFE – PFE signal is/was low – PFE | ||
| 32 | (R) | EVP – EGR not responding properly during test – EVP |
| (O,R,M) | EVR – EVP signal is/was low – EVR | |
| (R,M) | PFE – PFE shows low pressure, EGR not seating or memory, not seating intermittently – PFE | |
| 37 | (O,M) | ALL – EGR did not open/ respond during test or if memory code, did not open intermittently – EVP EVR PFE |
| 34 | (R) | EVP – EGR did not respond properly during test – EVP |
| (O,R,M) | EVR – EVP sensor is/was high – EVR | |
| PFE – PFE sensor is/was out of range – PFE | ||
| 35 | (R) | EVP – Engine RPM’s too low to test EGR system – EVP |
| (O,R,M) | EVR – EVP sensor signal is/was high – EVR | |
| PFE – PFE sensor signal is/was high – PFE | ||
| 38 | Idle Tracking Switch signal was intermittent – ISC | |
| 39 | Transmission Torque Converter clutch not engaging – Transmissions | |
| 41 | (R) | System lean – Fuel control |
| (M) | System was lean for 15 seconds or more (no HO2S switching) – Fuel control | |
| 42 | (R) | System rich – Fuel control |
| (M) | System was rich for 15 seconds or more (no HO2S switching) – Fuel control | |
| 43 | (R) | HO2S sensor not reading (run at 2000 rpm’s for 2 minutes and retest – check for HO2S switching) |
| (M) | Was lean at WOT for 3 seconds or more – Fuel control | |
| 44 | AIR system inoperative – Air Injection | |
| 45 | AIR not Diverting (AIRD) – Air Injection | |
| Electronic Ignition – coil primary circuit failure – Ignition Systems | ||
| 46 | AIR Bypass (AIRB) not working – Air Injection | |
| Electronic Ignition – primary circuit failure coil 2 – Ignition Systems | ||
| 47 | Low flow unmetered air (check for small vacuum leaks, injector o’rings, gaskets etc ) | |
| E4OD transmission 4×4 switch/circuit problem – Transmissions | ||
| 48 | High flow unmetered air (check for large vacuum leak, inlet hoses etc ) | |
| Electronic Ignition – coil primary circuit failure – Ignition Systems | ||
| 49 | Electronic Ignition – spout signal circuit problem – Ignition Systems | |
| Transmission 1/2 shift problem – Transmissions | ||
| 51 | Engine Coolant Temperature (ECT) sensor signal is/was too high – ECT | |
| 52 | Power Steering Pressure Switch/circuit open – PSP | |
| (R) | Did you turn wheel during test ? | |
| 53 | Throttle Position sensor too high – TPS | |
| 54 | Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal high – IAT VAT | |
| 55 | No or low (under 7 5 V) Key Power to PCM pin 5 | |
| 56 | Vane Air Flow (VAF) or Mass Air Flow (MAF) sensor high – VAF MAF | |
| Transmission Oil Temperature sensor too high – Transmissions | ||
| 57 | Intermittent in Park/Neutral/ Switch or Neutral Pressure switch circuit – PNP or Transmissions | |
| 58 | Idle Tracking Switch (ITS) signal problem ISC | |
| Vane Air Temperature (VAT) sensor out of range or open – VAT | ||
| 59 | AXOD 4/3 circuit fault – Transmissions | |
| 3 0L SHO – Low speed fuel pump circuit problem – Power / Fuel Pump Circuits | ||
| Transmission 2/3 shift problem – Transmissions | ||
| 61 | Engine Coolant Temperature (ECT) sensor is or was too low – ECT | |
| 62 | AXOD (KOEO only) 3/2 circuit short to ground – Transmissions | |
| AXOD (KOEO AND KOER) 4/3 circuit failure – Transmissions | ||
| E4OD excessive converter clutch slippage – Transmissions | ||
| 63 | Throttle Position Sensor (TPS) signal too low TPS | |
| 64 | Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal low or grounded – IAT VAT | |
| 65 | Check intermittent HO2S (signal or ground) – Fuel Control | |
| (R) | E4OD truck – cycle OD cancel switch after engine ID is received – Transmissions | |
| 1984 3 8L ONLY – O, M Battery voltage high (check for electrical system overcharging) | ||
| 66 | Vane Air Flow (VAF) or Mass Air Flow (MAF) signal low – VAF MAF | |
| Transmission Oil Temperature (TOT) signal low (possibly grounded) – Transmissions | ||
| 67 | Park/Neutral circuit fault – PNP | |
| Transmission Manual Lever Position (MLP) sensor circuit – Transmissions | ||
| (M) | Intermittent Park Neutral Position (PNP) sensor fault – PNP | |
| 68 | Idle Tracking Switch (ITS) circuit (possibly grounded) – ISC | |
| Vane Air Temperature (VAT) sensor out of range or grounded – VAT | ||
| 3 8L AXOD -Transmission Temperature Switch (TTS) open – Transmissions | ||
| Electronic Transmission – Transmission Oil Temperature (TOT) sensor was overheated -Transmissions | ||
| 69 | AXOD transmission (O) 3/2 switch closed (possible short circuit) – Transmissions | |
| AXOD (M) 3/2 switch open (poss short to power) – Transmissions | ||
| E4OD 3/4 shift problem – Transmissions | ||
| 70 | (M) | 3 8L AXOD – Data link to instrument cluster fault Service any other EEC codes, erase memory and retest If code is still present refer to instrument cluster diagnosis manual |
| 71 | (M) | 1 9L TBI, 2 3L TBI, 2 5L TBI – ITS signal was grounded when throttle should have been opening ITS-ISC ISC motor problem or Idle Tracking Switch (ITS) signal wire shorted to ground – ISC |
| (M) | 1 9L MFI – PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem – VPWR Diagnosis | |
| (M) | 3 8L AXOD – Data link to instrument cluster fault – See code 70 | |
| 72 | (R) | No MAP or MAF change in “goose” test – retest, check for frequency or voltage change – MAP MAF |
| (M) | 1 9L MFI – VPWR circuit to PCM was intermittent – VPWR Diagnosis | |
| (M) | 2 3L T/C – PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem – VPWR Diagnosis | |
| (M) | 3 8L AXOD – Message center data link circuit fault – See code 70 | |
| 73 | (O) | Rerun test, if 73 is still output replace TPS |
| (R) | No Throttle Position Sensor (TPS) change in “goose” test Must get at least 25% throttle rotation – TPS | |
| 74 | Was brake depressed after engine ID was received ? | |
| Brake On Off (BOO) signal open or short to ground – BOO | ||
| 75 | Brake On Off (BOO) signal shorted to power – BOO | |
| 76 | Vane Air Flow (VAF) did not respond to “goose” test – VAF | |
| 77 | System did not receive “goose” test – see TESTS | |
| 78 | (M) | VPWR circuit to PCM was intermittent or the PCM is bad VPWR Diagnosis |
| 79 | A/C is on or pin 10 is shorted to power | |
| 81 | Boost control solenoid – Solenoids | |
| AIRD solenoid – Solenoids and Air Injection | ||
| 3 0L SHO – Inlet Air Solenoid – Solenoids | ||
| 82 | 2 3L TC – Fan Control wire shorted to ground – A/C and Fan Circuits | |
| AIRB solenoid – Solenoids and Air Injection | ||
| 3 8L SC – Super Charger Bypass Solenoid – Solenoids | ||
| 83 | High Electro Drive Fan circuit fault – A/C and Fan Circuits | |
| EGR Control solenoid – Solenoids | ||
| 3 0L SHO – Low Speed Fuel Pump Relay circuit – Power / Fuel Pump Circuits | ||
| 84 | EGR Vacuum Regulator – Solenoids | |
| EGR cutoff solenoid – Solenoids | ||
| EGR Vent solenoid – Solenoids | ||
| 85 | 2 3L T/C Automatic – 3/4-4/3 Shift solenoid – Transmissions | |
| CANP solenoid (ALL 1989) – Solenoids | ||
| (M) | 1 9L MFI – System has corrected rich condition – Fuel control | |
| 86 | 2 3L or 2 9L Truck – A4LD 3/4 shift solenoid – Transmissions | |
| (M) 1 9L MFI – System has corrected lean condition – Fuel control | ||
| 87 | (O) | Fuel pump circuit fault (check inertia switch) – Power / Fuel Pump Circuits |
| Vehicles with 2BBL carb – Temperature Compensated Accelerator Pump Solenoid – Solenoids (M) intermittent in fuel pump primary circuit – Power / Fuel Pump Circuits NOTE: On some Escorts with automatic seat belts this code is normal IN MEMORY due to the wiring | ||
| 88 | Throttle Kicker Solenoid – Solenoids | |
| Variable Voltage Choke relay circuit fault – VVC | ||
| Fan Control circuit fault – A/C and Fan Circuits | ||
| A4LD – Converter Clutch Override solenoid – Transmissions | ||
| Electronic Ignition – IDM, DPI or spout circuit fault – Ignition Systems | ||
| 89 | A4LD – Converter Clutch Override solenoid – Transmissions | |
| AXOD Torque Converter Control solenoid circuit – Transmissions | ||
| Exhaust Heat Control (heat riser) solenoid circuit – Solenoids | ||
| 91 | (R, M) | System running lean – Fuel control |
| Transmission SS 1 circuit/solenoid problem – Transmissions | ||
| 92 | (R) | System running rich – Fuel control |
| Transmission SS 2 circuit/solenoid problem – Transmissions | ||
| 93 | (O,R) | Throttle linkage binding or bad ISC motor ISC HO2S not reading Fuel control |
| Transmission TCC circuit/solenoid problem – Transmissions | ||
| 94 | AIR system inoperative – Air Injection | |
| Transmission TCC circuit/solenoid problem – Transmissions | ||
| 95 | (O) | Fuel pump: open, bad ground or always on – Power / Fuel Pump Circuits |
| (R) | AIR not Diverting (AIRD) – Air Injection | |
| (M) | Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM (Fuel Pump Monitor signal) – Power / Fuel Pump Circuits | |
| 96 | (O) | Fuel pump monitor circuit shows no power – Power / Fuel Pump Circuits |
| (R) | AIR Bypass (AIRB) not working – Air Injection | |
| (M) | (Service 87 code first if present) Fuel pump relay or battery power feed was open – Power / Fuel Pump Circuits | |
| 97 | E4OD OD cancel light circuit failure – Transmissions | |
| 98 | (R) | Did not pass KOEO yet (Get 11 in KOEO first) |
| Transmission EPC circuit/solenoid failure – Transmissions | ||
| 99 | (R) | ISC needs to learn (Let idle for 2 minutes, Erase memory and retest) |
| Transmission EPC circuit/solenoid failure – Transmissions | ||
| 111 | System checks OK | |
| 112 | (O,M) | Intake Air Temperature (IAT) sensor is/was low or grounded – IAT |
| 113 | (O,M) | IAT sensor is/was high or open – IAT |
| 114 | (O,R) | IAT sensor out of range – IAT |
| 116 | (O,R) | Engine Coolant (ECT) sensor out of range – ECT |
| 117 | (O,M) | ECT sensor is/was low or grounded – ECT |
| 118 | (O,M) | ECT sensor is/was high or open – ECT |
| 121 | (O,R,M) | Throttle Position (TP) sensor out of range – TPS |
| 122 | (O,M) | TP low (possibly grounded or open circuit) – TPS |
| 123 | (O,M) | TP is/was high or short to power – TPS |
| 124 | (M) | TP voltage was higher than expected – Fuel control |
| 125 | (M) | TP voltage was lower than expected – Fuel control |
| 126 | (O,R,M) | MAP or BARO sensor out of range – “>MAP |
| 128 | (M) | MAP vacuum has not been changing – check vacuum lines – “>MAP |
| 129 | (R) | No MAP or Mass Air Flow sensor change during “goose” test – MAP MAF |
| 136 | (R) | Oxygen sensor not switching/system lean Left or Front HO2S – Fuel control |
| 137 | (R) | Oxygen sensor not switching/system rich Left or Front HO2S – Fuel control |
| 138 | (R) | Fault in Cold Start Injector circuit – Fuel control |
| 139 | (M) | Oxygen sensor not switching Left or Front HO2S – Fuel control |
| 144 | (M) | Oxygen sensor not switching Single, Right or Rear HO2S – Fuel control |
| 157 | (R,M) | Mass Air Flow signal is/was low or grounded – MAF |
| 158 | (O,R,M) | MAF sensor is/was high or short to power – MAF |
| 159 | (O,R) | MAF sensor is/was out of range – MAF |
| 167 | (R) | No Throttle Position sensor change in “goose” test (must get at least 25% rotation) – TPS |
| 171 | (M) | Oxygen sensor not switching – system was at adaptive limits – Single, Right or Rear HO2S – Fuel control |
| 172 | (R,M) | Oxygen sensor not switching – system is or was lean – Single, Right or Rear HO2S – Fuel control |
| 173 | (R,M) | Oxygen sensor not switching – system is or was rich – Single, Right or Rear HO2S – Fuel control |
| 174 | (M) | Oxygen sensor was slow in switching Single, Right or Rear HO2S – Fuel control |
| 175 | (M) | Oxygen sensor not switching – system was at adaptive limits – Left or Front HO2S – Fuel control |
| 176 | (M) | Oxygen sensor not switching – system is or was lean Left or Front HO2S – Fuel control |
| 177 | (M) | Oxygen sensor not switching – system was rich Left or Front HO2S – Fuel control |
| 178 | (M) | Oxygen sensor was slow in switching Left or Front HO2S – Fuel control |
| 179 | (M) | Fuel system was rich at part throttle Single, Right or Rear HO2S – Fuel control |
| 181 | (M) | Fuel system was lean at part throttle Single, Right or Rear HO2S – Fuel control |
| 182 | (M) | Fuel system was rich at idle Single, Right or Rear HO2S – Fuel control |
| 183 | (M) | Fuel system was lean at idle Single, Right or Rear HO2S – Fuel control |
| 184 | (M) | Mass Air (MAF) output higher than expected – Fuel control |
| 185 | (M) | Mass Air (MAF) output lower than expected – Fuel control |
| 186 | (M) | Injector pulse width longer than expected or Mass Air Flow (MAF) lower than expected – Fuel control |
| 187 | Injector pulse width shorter than expected or Mass Air Flow (MAF) higher than expected – Fuel control | |
| 188 | (M) | Fuel system was rich at part throttle – Left or Front HO2S – Fuel control |
| 189 | (M) | Fuel system was lean at part throttle – Left or Front HO2S – Fuel control |
| 191 | (M) | Fuel system was rich at idle – Left or Front HO2S – Fuel control |
| 192 | (M) | Fuel system was lean at idle – Left or Front HO2S – Fuel control |
| 193 | Failure in Flexible Fuel (FF) sensor circuit – Fuel control | |
| 194 | (M) | Perform cylinder balance test to check for inoperative injectors |
| 195 | (M) | Perform cylinder balance test to check for inoperative injectors |
| 211 | (M) | Ignition PIP signal was erratic or missing – Ignition Systems |
| 212 | (M) | Ignition TACH signal was erratic (module/wiring) or SPOUT circuit fault – Ignition Systems |
| 213 | (R) | Ignition SPOUT or SAW circuit open or shorted – Ignition Systems |
| 214 | (M) | Error in Cylinder ID (CID) circuit or signal – Ignition Systems |
| 215 | (M) | Primary circuit failure – ignition coil 1 – Ignition Systems |
| 216 | (M) | Primary circuit failure – ignition coil 2 – Ignition Systems |
| 217 | (M) | Primary circuit failure – ignition coil 3 – Ignition Systems |
| 218 | (M) | IDM signal open or high or left coil pack failure – Ignition Systems |
| 219 | (M) | SPOUT circuit failure, timing defaulted to 10 degrees – follow code 213 diagnosis |
| 222 | (M) | IDM open or high or right coil pack failure – Ignition Systems |
| 223 | (M) | Dual Plug (DPI), SPOUT or IDM circuit fault – Ignition Systems |
| 224 | (M) | Failure in ignition coil primary circuit – Ignition Systems |
| 225 | (R) | Knock sensor not tested (ignore if not pinging) – KS |
| 226 | (O) | Ignition Diagnostic Monitor (IDM) signal fault – Ignition Systems |
| 232 | (M) | EI primary coil circuit failure – Ignition Systems |
| 238 | (M) | EI primary circuit failure – ignition coil 4 – Ignition Systems |
| 311 | (R) | AIR system not working – Single, Right or Rear HO2S – Air Injection |
| 312 | (R) | AIR not diverting – Air Injection |
| 313 | (R) | AIR not bypassing – Air Injection |
| 314 | (R) | AIR inoperative, Left or Front HO2S – Air Injection |
| 326 | (R,M) | Pressure Feedback EGR shows low pressure EGR not seating or not seating intermittantly – PFE |
| 327 | (O,R,M) | EGR feedback signal is/was low – EVR or PFE |
| 328 | (O,R,M) | EGR Valve Position (EVP) is/was low – EVR |
| 332 | (R,M) | EGR did not open/respond during test or if memory code, did not open intermittantly – EVR or PFE |
| 334 | (O,R,M) | EVP sensor is/was high – EVR |
| 335 | (O) | EGR feedback signal is/was out of range – EVR or PFE |
| 336 | (O,R,M) | PFE sensor signal is/was was high – “>PFE |
| 337 | (O,R,M) | EGR feedback signal is/was was high – EVR |
| 338 | (M) | Cooling system did not heat up (check cooling system / thermostat operation) |
| 339 | (M) | Cooling system overheated (check cooling system / thermostat operation) |
| 341 | (O) | Octane jumper installed (information only code to notify you if it is installed) |
| 411 | (R) | Idle speed system not controlling idle properly (generally idle too high) – ISC |
| 412 | (R) | Idle speed system not controlling idle properly (generally idle too low) – ISC |
| 452 | (M) | Vehicle Speed Sensor (VSS) problem |
| 511 | (O) | No power to PCM pin 1 or bad PCM (processor) |
| 512 | (M) | Memory power (PCM pin 1) was interrupted – Was battery disconnected ? |
| 513 | (O) | Replace processor (PCM) (internal failure) |
| 519 | (O) | PSP switch/circuit open – PSP h Pedal Position (CPP) circuit fault – PNP |
| 528 | (M) | System shows voltage at pin 10 (is A/C on ?) or pin 30 (PNP, CPP switch) – PNP |
| 529 | (M) | Data Communications Link to processor failure Service any EEC codes, erase memory and retest If code is still present refer to instrument cluster diagnosis manual |
| 533 | (M) | Data Communications Link to instrument cluster failure – see 529 |
| 536 | (O,R,M) | Brake On Off open or shorted to ground – BOO |
| 538 | (R) | System did not receive “goose” test – TESTS |
| 539 | (O) | System shows voltage at PCM pin 10 Is A/C on ? |
| 542 | (O,M) | Fuel pump open, bad ground or always on – – Power / Fuel Pump Circuits |
| 543 | (O) | Fuel pump monitor circuit shows no power – Power / Fuel Pump Circuits |
| (M) | (Service 556 code first if present) Fuel pump relay or battery power feed was open – Power / Fuel Pump Circuits | |
| 551 | Problem in Intake Manifold Runner Control (IMRC) solenoid/circuit – Solenoids | |
| 552 | (O) | AIRB solenoid/circuit failure – Solenoids |
| 553 | (O) | AIRD solenoid/circuit failure – Solenoids |
| 554 | (O) | Fuel Press Regulator Control solenoid/circuit fault – Power / Fuel Pump Circuits |
| 556 | (O,M) | Fuel pump relay primary circuit fault – Power / Fuel Pump Circuits |
| 557 | (O,M) | Low speed pump relay primary circuit fault – Power / Fuel Pump Circuits |
| 558 | (O) | EGR vacuum regulator solenoid/circuit failure – EVR or PFE or Solenoids |
| 559 | (O) | A/C relay primary circuit fault – A/C and Fan Circuits |
| 563 | (O) | High Fan Control (HFC) circuit failure – A/C and Fan Circuits |
| 564 | (O) | Fan Control (FC) circuit failure – A/C and Fan Circuits |
| 565 | (O) | Canister Purge 1 solenoid/circuit failure – Solenoids |
| 566 | (O) | transmission 3/4 shift solenoid/circuit – Transmissions |
| 569 | (O) | Canister Purge 2 solenoid/circuit failure – Solenoids |
| 578 | (M) | A/C pressure sensor VREF short to ground – A/C and Fan Circuits |
| 579 | (M) | ACP sensor did not change with A/C on – A/C and Fan Circuits |
| 581 | (M) | Cooling fan current was excessive – A/C and Fan Circuits |
| 582 | (O) | Open cooling fan circuit – A/C and Fan Circuits |
| 583 | (M) | Fuel pump current was excessive – Power / Fuel Pump Circuits |
| 584 | (M) | Open power ground circuit – Power / Fuel Pump Circuits |
| 585 | (M) | A/C clutch current was excessive – A/C and Fan Circuits |
| 586 | (M) | Open circuit in A/C clutch – A/C and Fan Circuits |
| 587 | (O, M) | Communication problem between PCM and Variable Control Relay Module (VCRM) – Power / Fuel Pump Circuits |
| 617 | (M) | Transmission shift failure (1/2 shift) – Transmissions |
| 618 | (M) | Transmission shift failure (2/3 shift) – Transmissions |
| 619 | (M) | Transmission shift failure (3/4 shift) – Transmissions |
| 621 | (O) | Solenoid/circuit failure – shift solenoid 1 – Transmissions |
| 622 | (O) | Solenoid/circuit failure – shift solenoid 2 – Transmissions |
| 624 | (O,M) | Solenoid/circuit failure -Electronic Pressure Control (EPC) current is high – Transmissions |
| 625 | (O,M) | Solenoid/circuit failure – Electronic Pressure Control (EPC) current is low – Transmissions |
| 626 | (O) | Transmission Coast Clutch (CCS) Solenoid/circuit fault – Transmissions |
| 627 | (O) | Torque Converter Clutch circuit fault – Transmissions |
| 628 | (M) | Excessive converter clutch slippage – Transmissions |
| 629 | (O,M) | Torque Converter Clutch circuit fault – Transmissions |
| 631 | (O) | Overdrive Cancel Light circuit problem – Transmissions |
| 632 | (R) | E4OD – Transmission Control Switch (TCS) should be cycled once between engine ID and Goose test |
| 633 | (O) | 4x4L switch should be in 4×2 or 4×4 high for the test |
| 634 | (O,M) | Park/Neutral Position (PNP) or Clutch Pedal Position (CPP) circuit fault Electronic shift transmission – Manual Lever Position (MLP) sensor out of range in Park-Transmissions |
| 636 | (O,R) | Transmission Oil Temperature (TOT) sensor out of range – Transmissions |
| 637 | (O,M) | TOT sensor is/was high or open – Transmissions |
| 638 | (O,M) | TOT sensor is/was low or grounded – Transmissions |
| 639 | (R,M) | Transmission Speed sensor (TSS) circuit fault – Transmissions |
| 641 | (O) | Transmission solenoid/circuit failure Shift Solenoid 3 – Transmissions |
| 643 | (O,M) | Torque Converter Clutch (TCC) circuit – Transmissions |
| 645 | (M) | Transmission 1st gear failure – Transmissions |
| 646 | (M) | Transmission 2nd gear failure – Transmissions |
| 647 | (M) | Transmission 3rd gear failure – Transmissions |
| 648 | (M) | Transmission 4th gear failure – Transmissions |
| 649 | (M) | Transmission EPC system failure – Transmissions |
| 651 | (M) | Transmission EPC solenoid/circuit fault – Transmissions |
| 652 | (O) | Torque Converter Clutch (TCC) circuit fault – Transmissions |
| 654 | (O) | Transmission selector not in PARK – Transmissions |
| 656 | (M) | Torque Converter Clutch (TCC) slip – Transmissions |
| 657 | (M) | Transmission temperature was excessive – Transmissions |
Acura & Honda OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 0 | Electronic control module (ECM) |
| 1 | Heated oxygen sensor A |
| 2 | Oxygen content B |
| 3 | Manifold absolute pressure |
| 4 | Crank position sensor |
| 5 | Manifold absolute pressure |
| 6 | Engine coolant temperature |
| 7 | Throttle position sensor |
| 8 | Top dead center sensor |
| 9 | No.1 cylinder position sensor |
| 10 | Intake air temperature sensor |
| 11 | Electronic control module (ECM) |
| 12 | Exhaust recirculation system |
| 13 | Barometric pressure sensor |
| 14 | Idle air control valve or bad ECM |
| 15 | Ignition output signal |
| 16 | Fuel Injector |
| 17 | Vehicle speed sensor |
| 19 | A/T lock-up control solenoid |
| 20 | Electric load detector |
| 21 | V-TEC control solenoid |
| 22 | V-TEC pressure solenoid |
| 23 | Knock sensor |
| 30 | A/T FI signal A |
| 30 | A/T FI signal B |
| 41 | Heated oxygen sensor heater |
| 43 | Fuel supply system |
| 45 | Fuel supply metering |
| 48 | Heated oxygen sensor |
| 61 | Front heated oxygen sensor |
| 63 | Rear heated oxygen sensor |
| 65 | Rear heated oxygen sensor heater |
| 67 | Catalytic converter system |
| 70 | Automatic transaxle |
| 71 | Misfire detected cylinder 1 |
| 72 | Misfire detected cylinder 2 |
| 73 | Misfire detected cylinder 3 |
| 74 | Misfire detected cylinder 4 |
| 75 | Misfire detected cylinder 5 |
| 76 | Misfire detected cylinder 6 |
| 80 | Exhaust recirculation system |
| 86 | Coolant temperature |
| 92 | Evaporative emission control system |
BMW OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 1000 | End of fault code blinkingness |
| 1444 | No codes stored |
| 1211 | DME control module/unit |
| 1215 | Mass air flow sensor |
| 1216 | Throttle potentiometer |
| 1218 | Output stage, group #1, DME 3.3.1 only |
| 1219 | Output stage, group #2, DME 3.3.1 only |
| 1221 | Oxygen (EGO) sensor #1 |
| 1212 | Oxygen (EGO) sensor #2 |
| 1222 | Lambda Control 1 or Oxygen sensor lean/rich control stop |
| 1213 | Lambda Control 2 |
| 1223 | Coolant temperature sensor |
| 1224 | Air temperature sensor |
| 1225 | Knock sensor #1, DME 3.3.1 only |
| 1226 | Knock sensor #2, DME 3.3.1 only |
| 1227 | Knock sensor #3 |
| 1228 | Knock sensor #4 |
| 1231 | Battery Voltage/DME Main Relay |
| 1232 | Throttle Idle Switch |
| 1233 | Throttle WOT Switch |
| 1234 | Speedometer A signal, DME 3.3.1 only |
| 1237 | A/C compressor cutoff DME 3.3.1 only |
| 1242 | A/C compressor signal DME 3.3.1 only |
| 1243 | Crankshaft Pulse Sensor |
| 1244 | Camshaft Sensor |
| 1245 | Intervention AEGS |
| 1247 | Ignition Secondary Monitor |
| 1251 | Fuel Injector 1 (or group 1) |
| 1252 | Fuel Injector 2 (or group 2) |
| 1253 | Fuel Injector 3 |
| 1254 | Fuel Injector 4 |
| 1255 | Fuel Injector 5 |
| 1256 | Fuel Injector 6 |
| 1257 | Fuel Injector 7 |
| 1258 | Fuel Injector 8 |
| 1261 | Fuel Pump Relay Control |
| 1262 | Idle Speed Actuator |
| 1263 | Purge Valve |
| 1264 | EGO Heater |
| 1265 | Fault Lamp (check engine) |
| 1266 | VANOS |
| 1267 | Air Pump Relay Control |
| 1271 | Ignition Coil 1 |
| 1272 | Ignition Coil 2 |
| 1273 | Ignition Coil 3 |
| 1274 | Ignition Coil 4 |
| 1275 | Ignition Coil 5 |
| 1276 | Ignition Coil 6 |
| 1277 | Ignition Coil 7 |
| 1278 | Ignition Coil 8 |
| 1281 | DME Control Unit Memory Supply |
| 1282 | Fault code memory |
| 1283 | Fuel injector output stage |
| 1286 | Knock control test pulse |
Audi OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 0000 | End of fault sequence |
| 1111 | Bad ground to Electronic Control Unit (ECU) or ECU failure-check grounds or replace ECU |
| 1119 | Transmission Range - Defective wiring. Check for break or short |
| 1213 | Vehicle Speed Sensor (VSS) - Check transmission speed sender wiring and the wiring of the instrument cluster |
| 1231 | Vehicle Speed Sensor (VSS) (G54) - Check transmission speed sender wiring and the wiring of the instrument cluster |
| 1232 | Throttle Position Actuator - Check defective actuator or wiring for break or short. |
| 2111 | Engine speed sender. (RPM) |
| 2112 | Ignition reference sender |
| 2113 | Hall sender - No speed signal from distributor; check Hall sensor and circuits or the air-flow sensor plate is not moving freely; adjust potentiometer or lever. |
| 2114 | Hall sender not on reference point or distributor out of position. |
| 2121 | Idle switch - check switch & circuit. |
| 2122 | Hall sender - Check wiring for break or short. |
| 2123 | Full throttle switch; check switch & circuit. |
| 2132 | Electronic Control Module (ECM) - No ignition to injection signal. |
| 2141 | Knock sensor 1 control at maximum retard - test compression, change octane, adjust timing, check knock-sensor wires. |
| 2142 | Knock sensor 1 signal - Test sensor, check wiring for break or short. |
| 2143 | Knock sensor 2 control at maximum retard - test compression, change octane, adjust timing, check knock-sensor wires. |
| 2144 | Knock sensor 2 signal; test sensor. |
| 2212 | Throttle Potentiometer - Value out of range. |
| 2214 | RPM Signal - Idle speed to high or engine over-revved |
| 2221 | Vacuum Control - No vacuum to control unit. Check for leaks. |
| 2222 | Manifold Vacuum - Check vacuum line and waste gate for leaks. Pressure sensor - Sensor defective |
| 2223 | Altitude Sensor - Check sensor, check wiring for break or short. |
| 2224 | Turbo/Manifold pressure - Check turbo control wiring, check for over boost, air leak, defective waste gate valve, vacuum leak or defective pressure sensor. |
| 2231 | Idle-speed stabilizer adjustment limits exceeded; too-fast idle. Adjust throttle for full closing, check for vacuum leak, check ignition timing. Or air Mass Sensor - Check sensor and wiring. |
| 2232 | Air mass/flow sensor - No signal. Check wiring for break or short. |
| 2233 | Air mass/flow sensor reference voltage open or short circuit |
| 2234 | ECM Supply voltage low. |
| 2242 | CO-potentiometer voltage low |
| 2312 | Coolant temperature sensor - Check wiring, check resistance. |
| 2314 | Transmission to Engine control module circuit. - Check wires for breaks or shorts. |
| 2322 | Intake Air Temperature Sensor - Check sensor and wiring. |
| 2323 | Mass Airflow Sensor - Check sensor and wiring for breaks. |
| 2324 | Mass Airflow Sensor - Check sensor and wiring for breaks or shorts to B+ or ground or check for air leak. |
| 2331 | Oxygen Sensor Control - Out of range. - Check ignition, air intake for leaks and injectors. |
| 2332 | Oxygen Sensor - Bank 2 - Check wiring for breaks or shorts. |
| 2341 | Oxygen sensor (O2) at control limit; check CO, lambda-sensor wire, lambda-sensor control, start valve, evaporative system and check for vacuum leaks. |
| 2342 | Oxygen Sensor Control - no signal - Check wiring, sensor. |
| 2343 | Rich limit; the pressure regulator has exceeded +10 mA for more than 5 minutes, closed-loop; check for vacuum leaks. |
| 2344 | Lean limit; the pressure actuator has exceeded -5mA for more than 5 minutes, closed loop; check idle. |
| 2411 | EGR System Malfunction |
| 2412 | Intake Air Temperature Sensor - Check sensor and wiring for breaks or shorts |
| 2413 | Mixture Control - Running rich |
| Fuel pressure too low | |
| 3424 | Malfunction Indicator Lamp (MIL) failure - Check lamp and wiring. |
| 4311 | Secondary Air Injection Pump Relay - Check relay and wiring. |
| 4312 | EGR Frequency Valve |
| 4313 | Secondary Air Injection Solenoid Valve - Check valve and wiring. |
| 4331 | EVAP Carbon Canister Solenoid Purge Valve 2 |
| 4332 | Ignition Circuit Final Stage - Check for breaks or short to ground or B+ or bad ECM. |
| 4343 | EVAP Carbon Canister Solenoid Purge Valve 1 |
| 4411 | Fuel Injector Cylinder 1 or 1 & 5 |
| 4412 | Fuel Injector Cylinder 2 or 2 & 7 |
| 4413 | Fuel Injector Cylinder 3 or 3 & 6 |
| 4414 | Fuel Injector Cylinder 4 or 4 & 8 |
| 4421 | Fuel Injector Cylinder 5 |
| 4422 | Fuel Injector Cylinder 6 |
| 4423 | Fuel Injector Cylinder 7 |
| 4424 | Fuel Injector Cylinder 8 |
| 4431 | Idle Air Control Valve / Idle Stabilizer - Check valve and wiring. |
| 4433 | Fuel Pump Relay |
| 4442 | Waste gate - Defective frequency valve or wiring. |
| Boost pressure circuit - Check for short. | |
| 4443 | EVAP Canister purge valve. |
| 4444 | No fault in system. |
Nissan OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | Crank Angle Sensor/Camshaft Position Sensor |
| 12 | Air Flow Meter/Mass Air Flow Sensor |
| 13 | Engine Coolant Temperature Sensor |
| 14 | Vehicle Speed Sensor |
| 21 | Ignition Signal |
| 22 | Fuel Pump |
| 23 | Idle Switch |
| 24 | Throttle Valve Switch |
| 25 | Idle Speed Control Valve |
| 28 | Cooling Fan Circuit |
| 31 | ECM |
| 32 | EGR Function |
| 33 | Heated Oxygen Sensor |
| 34 | Knock Sensor |
| 35 | Exhaust Gas Temperature Sensor |
| 36 | EGR Control-Back Pressure Transducer |
| 37 | Knock Sensor |
| 38 | Right hand bank Closed Loop (B2) |
| 41 | Intake Air Temperature Sensor |
| 42 | Fuel Temperature Sensor |
| 43 | Throttle Position Sensor |
| 44 | ECCS Normal Operation |
| 45 | Injector Leak |
| 47 | Crankshaft Position Sensor |
| 51 | Injector Circuit |
| 53 | Oxygen Sensor |
| 54 | A/T Control |
| 55 | No Malfunction |
| 63 | No. 6 Cylinder Misfire |
| 64 | No. 5 Cylinder Misfire |
| 65 | No. 4 Cylinder Misfire |
| 66 | No. 3 Cylinder Misfire |
| 67 | No. 2 Cylinder Misfire |
| 68 | No. 1 Cylinder Misfire |
| 71 | Random Misfire |
| 72 | TWC Function right hand bank |
| 76 | Fuel Injection System Function right hand bank |
| 77 | Rear Heated Oxygen Sensor Circuit |
| 82 | Crankshaft Position Sensor |
| 84 | A/T Diagnosis Communication Line |
| 85 | VTC Solenoid Valve Circuit |
| 86 | Fuel Injection System Function right hand bank |
| 87 | Canister Control Solenoid Valve Circuit |
| 91 | Front Heated Oxygen Sensor Heater Circuit right hand bank |
| 94 | TCC Solenoid Valve |
| 95 | Crankshaft Position Sensor |
| 98 | Engine Coolant Temperature Sensor |
| 101 | Front Heated Oxygen Sensor Heater Circuit right hand bank |
| 103 | Park/Neutral Position Switch Circuit |
| 105 | EGR and EGR Canister Control Solenoid Valve Circuit |
| 108 | Canister Purge Control Valve Circuit |
Lexus OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 12 | RPM Signal |
| 13 | RPM Signal |
| 14 | Ignition Signal |
| 15 | Ignition Signal |
| 16 | Electronically Controlled Transmission Control Signal |
| 17 | CMP No. 1 |
| 18 | CMP No. 2 |
| 21 | Main O2S & Heater Signal |
| 22 | ECT Sensor Signal |
| 24 | IAT Sensor Signal |
| 25 | Air–Fuel Ratio Lean Malfunction |
| 26 | Air–Fuel Ratio Rich Malfunction |
| 27 | Sub O2S Signal |
| 28 | Main O2S |
| 29 | Sub O2S |
| 31 | Air Flow Meter Signal |
| 32 | Air Flow Meter Signal |
| 35 | HAC/Barometric Pressure Sensor Signal |
| 41 | TP Sensor Signal |
| 42 | VSS Signal |
| 43 | Starter Signal |
| 47 | Sub TP Sensor |
| 48 | Secondary Injection System Malfunction |
| 51 | Switch Condition Signal |
| 52 | KS Signal |
| 53 | Knock Control Signal |
| 55 | KS Signal |
| 70 | EGR System Malfunction |
| 71 | EGR System Malfunction |
| 78 | Fuel Pump Control |
Subaru OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | No signal entered from crank angle sensor but signal entered from cam angle sensor |
| 12 | Too low or too high voltage signal emitted from ignition (starter) switch |
| 13 | No signal entered from cam angle sensor but signal entered from crank angle sensor |
| 14 | Fuel injector #1 inoperative (too low or too high voltage signal emitted from monitor circuit) |
| 15 | Fuel injector #2 inoperative (too low or too high voltage signal emitted from monitor circuit) |
| 16 | Fuel injector #3 inoperative (too low or too high voltage signal emitted from monitor circuit) |
| 17 | Fuel injector #4 inoperative (too low or too high voltage signal emitted from monitor circuit) |
| 21 | Too low or too high voltage from water temperature sensor |
| 22 | Too low or too high voltage produced in knock sensor monitor circuit |
| 23 | Too low or too high voltage input entered from air flow sensor |
| 24 | Air control valve inoperative (too low or too high voltage signal produced in monitor circuit) |
| 26 | Air temperature sensor fault |
| 31 | Too low or too high voltage input entered from throttle sensor |
| 32 | Oxygen sensor inoperative |
| 33 | Too low or too high voltage input entered from speed sensor |
| 35 | Solenoid valve inoperative |
| 36 | Ignition circuit fault |
| 41 | Faulty learning control function, or adaptive fuel control exceeded limits |
| 42 | Too low or too high voltage input entered from idle switch |
| 43 | Throttle switch fault |
| 44 | Waste gate control solenoid valve inoperative (Turbo only) |
| 45 | Faulty sensor (BARO) |
| Faulty sensor or pressure exchange solenoid valve inoperative (Turbo only) | |
| 49 | Use of improper air flow sensor |
| 51 | Too low or too high voltage signal entered from neutral switch |
| Too low or too high voltage signal entered from inhibitor switch | |
| 52 | Too low or too high voltage signal entered from parking switch |
| 62 | Electric load signal fault |
| 63 | Blower fan switch fault |
| 65 | Vacuum pressure sensor fault |
Mazda OBD1 Diagnostic Code
| Code | Meaning/Fault Locations |
|---|---|
| 1 | Ignition pulse missing |
| 2 | Diesel: Engine speed (RPM) sensor – no signal |
| Petrol: Crankshaft position (CKP) sensor/engine speed (RPM) sensor – no signal | |
| 3 | Camshaft position (CMP) sensor – no signal |
| 4 | Diesel: Crankshaft position (CKP) sensor – no signal |
| Petrol: Crankshaft position (CKP) sensor/engine speed (RPM) sensor – no signal | |
| 5 | Knock sensor (KS) |
| 6 | Vehicle speed sensor (VSS) |
| 8 | Mass air flow (MAF) sensor/volume air flow (VAF) sensor |
| 9 | Engine coolant temperature (ECT) sensor |
| 10 | Intake air temperature (IAT) sensor |
| 11 | Intake air temperature (IAT) sensor |
| 12 | Throttle position (TP) sensor |
| 14 | Barometric pressure (BARO) sensor |
| 15 | Except V6: Oxygen sensor (O2S)/heated oxygen sensor (HO2S) – no activity |
| V6: Heated oxygen sensor (HO2S), bank 2 – no activity | |
| 16 | Exhaust gas recirculation (EGR) valve position sensor |
| 17 | Except V6: Oxygen sensor (O2S)/heated oxygen sensor (HO2S) – incorrect signal |
| V6: Heated oxygen sensor (HO2S), bank 2 – incorrect signal | |
| 18 | Fuel quantity adjuster |
| 19 | Fuel quantity adjuster position sensor |
| 22 | Fuel shut-off solenoid |
| 23 | Diesel: Fuel temperature sensor |
| Petrol: Heated oxygen sensor (HO2S), bank 1 – no activity | |
| 24 | Heated oxygen sensor (HO2S), bank 1 – incorrect signal |
| 25 | Fuel pressure regulator control solenoid |
| 26 | Evaporative emission (EVAP) canister purge valve |
| 28 | Exhaust gas recirculation (EGR) solenoid – vacuum |
| 29 | Exhaust gas recirculation (EGR) solenoid – vent |
| 34 | Idle air control (IAC) valve |
| 35 | Fuel pressure regulator control solenoid 2 |
| 36 | Glow plug relay |
| 41 | Intake manifold air control solenoid 1 |
| 43 | Fuel injection timing sensor |
| 46 | Petrol: Intake manifold air control solenoid 2 |
| Diesel: Closed throttle position (CTP) switch | |
| 49 | Engine control module (ECM) – defective |
| 52 | Module coding plug |
| 55 | Input shaft speed (ISS) sensor/turbine shaft speed (TSS) sensor |
| 56 | 323: Engine control module (ECM) – supply voltage |
| 626: Transmission fluid temperature (TFT) sensor | |
| 57 | Engine control relay |
| 60 | Shift solenoid (SS) A, 1-2 |
| 61 | Shift solenoid (SS) B, 2-3 |
| 62 | Shift solenoid (SS) C, 3-4 |
| 63 | Torque converter clutch (TCC) control solenoid |
| 64 | Shift timing solenoid, 3-2 |
| 65 | Torque converter clutch (TCC) solenoid |
| 66 | Transmission fluid pressure (TFP) solenoid |
| 67 | Engine coolant blower motor relay – low temperature |
| 68 | Engine coolant blower motor relay – high temperature |
| 69 | Engine coolant blower motor temperature sensor |
| 71 | Engine control module (ECM)/immobilizer control module – communication error |
| 72 | Ignition key – not programmed into ECM |
| 73 | Engine control module (ECM)/immobilizer control module – immobilizer codes do not match |
| 74 | Engine control module (ECM)/immobilizer control module – ignition key codes not match |
| 75 | Engine control module (ECM) – EEPROM error |
| 76 | Engine control module (ECM) – immobilizer code not stored |
| 77 | Immobilizer control module – communication error |
Toyota OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 1 | Normal Condition. |
| 2 | Air Flow Meter signal. |
| 3 | Ignition signal. |
| 4 | Engine Coolant Temperature Sensor signal. |
| 5 | Oxygen Sensor. |
| 6 | RPM signal (Crank Angle Pulse). |
| 7 | Throttle Position Sensor signal. |
| 8 | Intake Air Temperature Sensor signal. |
| 9 | Vehicle Speed Sensor signal. |
| 10 | Starter signal. |
| 24 | Switch signal. |
| Momentary interruption in power supply to ECU (electronic control unit or computer) up to 1991 | |
| 12 | Engine revolution signal missing |
| 13 | RPM signal to ECU missing above 1000 rpm |
| 14 | Igniter signal to ECU missing |
| 16 | A/T control signal missing from ECU |
| 21 | Main oxygen sensor signal fault |
| 22 | Water temperature sensor circuit fault |
| 23 | Intake air temperature signal fault |
| 24 | Intake air temperature signal fault |
| 25 | Air/fuel ratio LEAN |
| 26 | Air/fuel ratio RICH |
| 27 | Sub-oxygen sensor signal or heater circuit fault |
| 28 | No. 2 oxygen sensor/heater signal fault |
| 52 | Too low or too high voltage signal entered from parking switch |
| 31 | Air flow meter circuit or Vacuum sensor signal fault |
| 32 | Air flow meter circuit or Vacuum sensor signal fault |
| 34 | Turbo-charging pressure signal fault |
| 35 | Altitude compensation sensor signal fault |
| 36 | Turbo-charging pressure signal fault |
| 41 | Throttle position circuit fault |
| 42 | Vehicle speed sensor circuit |
| 43 | No starter signal to the ECU |
| 51 | AC signal on; DL contact off (in transmission shifter with diagnostic connector jumped) |
| 52 | Knock sensor fault Code 71 EGR system malfunction |
| 53 | Knock sensor fault Code 71 EGR system malfunction |
| 55 | Knock sensor fault Code 71 EGR system malfunction |
| 72 | Fuel cut solenoid signal fault |
| 78 | Fuel pump control signal fault |
| 81 | TCM communication fault |
| 83 | TCM communication fault |
| 84 | TCM communication fault |
| 85 | TCM communication fault |
Jeep OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | No crank reference signal detected during engine cranking. Intermittent loss of either camshaft or crankshaft position sensor. |
| 12 | Positive battery input to PCM was disconnected within the last 50 Key-on cycles. |
| 13 | No difference recognized between the engine MAP reading and the barometric (atmosphere) pressure reading from start-up. |
| 14 | MAP sensor input above or below acceptable voltage. 5 volt output to MAP sensor open. |
| 15 | No vehicle speed sensor signal detected during driving load conditions. |
| 17 | Engine did not reach operating temperature within acceptable limits |
| 21 | Upstream oxygen sensor response slower than minimum required switching frequency. |
| Upstream oxygen sensor heating element circuit malfunction. | |
| Downstream oxygen sensor heating element circuit malfunction. | |
| Downstream oxygen sensor input voltage maintained above the normal operating range. | |
| Oxygen sensor voltage too low, tested after cold start. (Upstream or Downstream) | |
| Left oxygen sensor input voltage maintained above the normal operating temperature. | |
| 22 | Engine coolant temperature sensor above or below acceptable voltage. |
| 23 | Intake air temperature sensor input above or below acceptable voltage. |
| 24 | Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor. |
| 25 | A shorted or open condition detected in one or more of the idle air control motor circuits. Actual idle speed does not equal target idle speed. |
| 27 | Injector #1 through 6, or any combination of individual injectors driver does not respond properly to the control signal. |
| 31 | An open or shorted condition detected in the A/C clutch relay circuit. Insufficient or excessive vapor flow detected during fuel evaporation emission system operation. |
| 33 | An open or shorted condition detected in the duty cycle purge solenoid circuit. (A/C clutch relay circuit) |
| 34 | An open or shorted condition detected in the Speed Control vacuum or vent solenoid circuits. Speed control switch input below the minimum acceptable voltage. |
| 37 | Relationship between engine speed and vehicle speed indicates no torque converter clutch engagement. |
| An open or shorted condition detected in the torque converter part throttle unlocks solenoid control circuit. | |
| Incorrect input state detected for the Park/Neutral switch. Auto only. | |
| 41 | An open or shorted condition in the generator field control circuit. |
| 42 | An open or shorted condition detected in the auto shutdown relay circuit. |
| An open condition detected in the ASD relay output circuit | |
| An open or shorted condition detected in the fuel pump relay control circuit | |
| An open circuit between PCM and fuel gauge sending unit. | |
| Circuit shorted to voltage between PCM and fuel gauge sending unit. | |
| No movement of fuel level sender detected. | |
| 43 | Peak primary circuit current not achieved with maximum dwell time |
| Misfire detected in one or more cylinders 1 thru 6. (4 and 6 cylinders.) | |
| 44 | Battery temperature sensor in voltage above or below acceptable range. |
| 46 | Battery voltage sense input above target charging voltage during engine operation. |
| 47 | Battery voltage sense input below target charging during engine operation. Also, no significant change detected in battery voltage during active test of generator output circuit. |
| 51 | A lean air/fuel mixture has been indicated by an abnormally rich correction factor. |
| 52 | A rich air/fuel mixture has been indicated by an abnormally rich correction factor. |
| 53 | PCM Internal fault condition detected. |
| 54 | No camshaft signal detected during engine cranking. |
| 55 | Completion of fault code display on Check Engine lamp. |
| 62 | PCM Failure to update service reminder indicator |
| 63 | Unsuccessful attempt to write to an EEPROM location by the PCM. |
| 64 | Catalyst efficiency below required level. (Same as code 72) |
| 65 | Power steering high pressure seen at high speed. (2.5L only) |
| 72 | Catalyst efficiency below required level. (Same as code 64) |
| 77 | Malfunction detected with poser feed to speed control servo solenoids |
Dodge OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | Timing belt skipped 1 tooth or more from initial learned value, Intermittent loss of either camshaft or crankshaft position sensor, No crank reference signal detected during engine cranking |
| 12 | Direct battery input to PCM was disconnected within the last 50 key-on cycles (normal) |
| 13 | Engine Coolant Temperature Sensor |
| 14 | No change in MAP from start to run |
| 15 | No vehicle speed sensor signal |
| 17 | Closed loop temp not reached or engine cold too long |
| 21 | Oxygen sensor problem, upstream or down stream |
| 22 | Engine coolant temp sensor out of range |
| 23 | Intake air temp sensor out of range |
| 24 | Throttle Position sensor out of range |
| 25 | Idle air control motor circuits, target idle not reached (+/- 200),vacuum leak found |
| 27 | Injector control circuit |
| 31 | EVAP purge flow monitor failure or EVAP solenoid circuit |
| 32 | EGR system failure |
| 33 | A/C clutch relay circuit |
| 34 | Speed control Solenoid circuits |
| 35 | Rad Fan control relay circuit |
| 37 | Torque converter clutch solenoid CKT or park/neutral switch failure |
| 41 | Generator field not switching properly |
| 42 | Fuel pump relay control CKT, Auto shutdown relay control CKT, No ASD relay output voltage at PCM, Fuel level sending unit volts out of range, Fuel level unit No change over miles |
| 43 | Multiple/ single cylinder misfire |
| 44 | Battery temp sensor volts out of range |
| 46 | Charging system voltage too low |
| 51 | Fuel system lean |
| 52 | Fuel system rich |
| 53 | Internal control failure |
| 54 | No Cam signal at PCM |
| 55 | End of error messages |
| 62 | PCM failure SRI mile not stored |
| 63 | PCM Failure EEPROM write denied |
| 64 | Catalytic Converter Efficiency Failure |
| 65 | Power steering switch failure |
Chrysler OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | Camshaft signal or ignition signal, no reference signal during cranking. |
| 12 | Memory to controller has been cleared within 50-100 engine starts. |
| 13 | MAP sensor not detecting any change during test. |
| 14 | MAP voltage too high or too low. |
| 15 | Vehicle speed sensor, no signal detected. |
| 16 | Knock sensor circuit. Open or short detected. |
| 17 | Low engine temperature, possible thermostat fault. |
| 21 | Oxygen sensor signal, neither rich nor lean detected. |
| 22 | Coolant sensor voltage low. |
| 23 | Air charge voltage high/low detected. |
| 24 | Throttle position sensor voltage high/low. |
| 25 | Automatic idle speed motor driver circuit, short or open detected. |
| 26 | Injectors 1 2 and 3 peak current not reached. |
| 27 | Injector control circuit does not respond to control signal. |
| 31 | Purge solenoid circuit, open or short detected. |
| 32 | EGR solenoid circuit, open or short detected. |
| 33 | A/C clutch relay circuit, open or short detected. |
| 34 | Speed control servo solenoid, open or short detected. |
| 35 | Radiator fan control relay circuit, open or short detected. |
| 36 | Waste-gate solenoid, open or short detected. |
| 37 | Part throttle unlock (PTU) circuit, open or short detected. |
| 41 | Charging system circuit not responding to control signal |
| 42 | Fuel pump or auto shutdown (ASD) relay voltage sensed at controller. |
| 43 | Ignition control circuit not responding. |
| 44 | Battery temperature voltage circuit problem. |
| 45 | Turbo boost limit exceeded-map sensor detects over-boost. |
| 46 | Battery voltage too high. |
| 47 | Battery voltage too low. |
| 51 | Air/fuel at limit. |
| 52 | Logic module fault. |
| 53 | Internal controller failure. |
| 54 | Camshaft reference circuit not detected. |
| 55 | End of error message. |
| 61 | BARO read solenoid, open or short detected. |
| 62 | EMR mileage not stored. |
| 63 | Eprom write denied. |
| 64 | Flex fuel sensor signal out of range. |
| 65 | Manifold tuning valve, open or short detected. |
| 66 | No CCD messages. |
| 76 | Ballast bypass relay, open or short detected. |
| 77 | Speed control relay, open or short detected. |
Saturn OBD1 Diagnostic Code
| Code | Meaning/Fault location |
|---|---|
| 11 | Transaxle codes present |
| 12 | Diagnostic check only |
| 13 | Oxygen sensor, circuit open or not ready |
| 14 | Coolant sensor/high temperature |
| 15 | Coolant sensor/low temperature |
| 17 | PCM fault – pull-up resistor |
| 19 | 6X signal fault (92-95 models) |
| 21 | Throttle position sensor-voltage high |
| 22 | Throttle position sensor-voltage low |
| 23 | IAT circuit low |
| 24 | VSS circuit-no signal |
| 25 | IAT circuit-Temp out of high range |
| 26 | Quad driver output fault |
| 32 | EGR system fault |
| 33 | MAP sensor – voltage out of range high |
| 34 | MAP sensor – voltage out of range low |
| 35 | IAC – rpm out of range |
| 41 | Ignition control circuit open or shorted |
| A EST circuit open | |
| B EST circuit shorted | |
| 42 | EST bypass, open or shorted |
| A Bypass circuit grounded | |
| B Bypass circuit open | |
| C Bypass circuit shorted | |
| 43 | Knock sensor circuit shorted or open |
| 44 | Oxygen sensor indicates system lean |
| 45 | Oxygen sensor indicates system rich |
| 46 | Power steering pressure switch circuit, open |
| 49 | Idle rpm out of limit high (vacuum leak) |
| 51 | PCM memory error |
| 55 | A/D convertor error in PCM |
| 81 | ABS message fault (1993+ vehicles with TCS) |
| 82 | PCM internal communication fault |
Final Thoughts
The introduction of the OBD1 system marked one of the greatest advancements in the automobile industry. Even though it was limited in functionality, the system paved the way for a more efficient and useful OBD2 system. OBD1 systems can be troublesome and very frustrating, but their significance is unforgettable.
This article has dealt with the meaning of OBD1 codes in many brands. You can now understand how they work and how to use them for your benefit. I hope you got all the answers you were looking for.
FAQs
How Can I Check GM OBD1 Codes Without Any Scanner?
Pay attention to the GM OBD1 connector schematic below. It shows the purpose of each slot on the connector. Be careful not to connect the wrong parts. What you will need to do to get the OBD1 codes is to short the circuit between pin A and pin B.
This process will enable the car to enter into a diagnostic mode by flashing the Check Engine Light a couple of times. The goal is to count the flashes, which will give us the OBD1 codes you need.
Follow these simple steps carefully to check the OBD1 codes on your GM car without any scanner:
Step 1: Make sure you have your car battery charger connected to avoid unnecessary error codes and diagnostic issues.
Step 2: Carefully place a jumper wire between pin B and pin A, making sure not to insert in the wrong pin.
Step 3: After letting the jumper wire stay put, turn the ignition ON, remembering not to start the engine.
Step 4: At this point, you may notice that the Check Engine Light has begun to flash. Start counting the flashes. In the presence of more than one OBD1 code, you will see longer pauses between codes and shorter pauses between the trouble code’s digits. This is to say that if the code is 14, you will notice one flash, a pause, and then four flashes. After all the DTCs are scanned, it will flash code 12, which is one flash, a pause, and then two flashes.
Step 5: Take note of all the OBD1 codes scanned and refer them to the OBD1 diagnostic codes list specific to the GM car you own. You can now remove the jumper wire and battery charger. You have finished checking the codes all on your own.
How Do I Know My Car Is OBD1 Or OBD2?
There are two ways of knowing if your car is OBD1 or OBD2.
The year and place it was manufactured or bought when new
Cars manufactured in the USA in and after 1996 have the OBD2 system. However, depending on the country and the market it was marketed for, your vehicle may have a different system from those of other cars made in the same year.
In Europe, most petrol cars sold new between 2001 and 2004 have an OBD2 system. However, most vans, trucks, and 4*4 vehicles in Europe were not using the OBD2 system till 2007. You can confirm the year your car was manufactured by looking up your model online. Below is a list of countries and years in which the vehicles in those countries became OBD2 compatible.
| Country | Year |
|---|---|
| United States | 1996 |
| European Union (Diesel) | 2007 |
| European Union (Petrol) | 2002 |
| Canada | 1998 |
| Australia (Diesel) | 2007 |
| Australia (Petrol) | 2006 |
| China (Petrol) | 2008 |
| China (Diesel) | 2011 |
| China (Petrol) | 2010 |
| Hong Kong | 2006 |
| Mexico | 2007 |
| Morocco | 2010 |
| New Zealand (Diesel) | 2007 |
| New Zealand (Petrol) | 2006 |
| Nigeria | 2015 |
| Peru | 2003 |
| Peru | 2017 |
| Philippines | 2016 |
| Singapore | 2014 |
| Taiwan | 2008 |
| Thailand | 2013 |
| Turkey | 2013 |
| United Arab Emirates | 2018 |
Check under the hood.
There is a sticker under the hood of every car that will show if your car is OBD2 compliant. It will look similar to the image shown below:
Can An OBD2 Scanner Read OBD1 Codes?
Unfortunately, it can’t. The OBD2 scanner is only matched with the OBD2 system. Even the adapter cable can’t change anything in the system. However, there are many professional scanners that are so advanced to use for scanning in both OBD1 and OBD2 vehicles, but the price will be expensive.
