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P1689 Cummins Engine Code: Meaning, Symptoms, Causes, Diagnostics, And Fixes

The P1689 OBD2 key for a specific diesel engine that is not injecting fuel. These numbers mean that there is no communication between the ECM and injection pump module data. The response comes from the ECM. It often happens if the driver is accelerating and the result is that the engine stalls.

P1689 Cummins Code Definition And Meaning (Technical Description)

  • P0012 Cummins: No Communication Between the ECM and the Injection Pump Module Data

Symptoms Of P1689 Cummins?

The Code: There are a few symptoms that occur if this response appears. One is that the check engine light ignites. The second is that the automobile does not accelerate when the gas pedal is pressed. Another symptom is that the engine stalls as the accelerator is pressed.

You might also notice a few other symptoms as you diagnose the issue. One is a decrease in gas-mileage efficiency. You might also notice low gas pressure, as the engine isn’t getting what it needs. You might also hear a whining noise in the rear of the truck as the part begins to fail.

Causes Of P1689 Cummins Engine Code?

When the ECM notices that the fuel injector is not working properly, it triggers the check engine light. The trouble could have originated in a faulty FPCM. It could also have started with an open harness or a short in the FPCM. The problem could also come from a weak electrical circuit connection in the pump controller module.

As the part helps power the engine, the car will not run properly if there is a predicament. The engine might stall. It might not accelerate, despite pushing the accelerator pedal. The issue could also fire if there is a fault with the Powertrain Control Module’s memory or programming. A hardware error in the PCM could trigger the reaction, too.

How Serious Is P1689 Cummins Code?

The issue is serious because it affects the way the engine runs. The ECM monitors the Fuel Pump Control Module (FPCM) at all times. The response could also be a problem with the Powertrain Control Module, which is also a serious issue. Both the control modules can be expensive to repair. The engine cannot run without these important modules functioning properly.

How To Diagnose And Fix The Code P1689 Cummins?

Tools

To determine the issue, you should use a scan tool to see what the number is. Then, look a second time with the scan tool to observe the freeze frame data. Also using the scan tool, look for the diagnostic trouble key. If you get a consistent answer, you will want to look at components in the engine. Having a flashlight is helpful to see if connectors are corroded.

Methods

Diagnosing the quandry involves using the ECM reader to get the reading. After receiving the answer, visually inspect the wiring harness and connectors near the broken part. Then, look for damaged components. The key response fires if connector pins are corroded. Look for bent or broken pins, if they aren’t corroded. Some connector pins might be pushed out, too.

If the trouble response consistently appears after checking the connectors and pins, look at the filter. You are looking for a gas pressure drop. If that is ok, then look at the transfer inlet where the gas is sent to the engine for a blockage.

You should also check the battery terminals to be sure that everything is properly connected. If there is a problem with the part, you might find oil or gas sputtering around the engine. If you lift the hood, you might see droplets splattered around the inside of the engine.

What Are Common Mistakes While Diagnosing Code P1689 Cummins?

There are several common mistakes as you are diagnosing this problem. One common issue is that the engine needs an oil change. This has very little to do with the setback. Another common misdiagnosis is fuel contamination. Some people misdiagnose the issue and install a new battery. The fault rarely has to do with the battery, unless a connector is bad or corroded.

Tips To Avoid P1689 Cummins In The Future?

When the trouble numbers appear, there is most likely a problem with the fuel pump. This can be an expensive repair. Fortunately, there are things you can do to keep your fuel pump working properly.

Firstly, you should use good fuel. If you use low-quality fuel, the fuel pump wears out from having to filter so many contaminents. Therefore, always follow your manufacturer’s recommendations for fuel.

Then, you should never run the vehicle on low fuel or let it get close to empty. When you run the car on low fuel, contaminants settle and begin to clog the part. Eventually, the fuel pump dies. Try to keep at least a quarter of a tank in the car at all times to protect the fuel pump and the engine.

Pay attention to the fuel filters and change them two to four times per year. The fuel filter does get blocked and not changing it reduces the pump’s performance. Debris builds up and blocks the filter; this can cause the piece to fail.

Do not use cheap additives in your fuel tank. Manufacturers often tout their additives as fuel pump protectors. But, if your vehicle works well, you don’t need additives. Just use the correct fuel octane as recommended by your vehicle manufacturer. Additives might corrode this piece and other sensitive engine parts.

Finally, you should occasionally clean your fuel tank. If you store your vehicle, moisture can get into the fuel tank and pump. Not driving your vehicle or driving it with low fuel causes sediment to build in the tank. Then, the tank can rust and the fuel pump can fail. Follow your manufacturer’s recommendation on the perfect time to clean these pieces.

Read more: P0016 Code: Meaning, Symptoms, Causes, Diagnostics, And Fixes

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