What Is P1689 Code On Dodge Cummins? (How to Fix It)

The P1689 OBD2 key is for a particular diesel engine that doesn’t inject fuel. These figures indicate that the ECM and injection pump module data are not communicating.

The ECM provides the answer. It frequently occurs as the driver accelerates, resulting in the engine stalling. Data from the ECM and the Injection Pump Module is not being sent.

The bad running symptoms are typical of a MAP sensor failure. Furthermore, in rare circumstances, a faulty MAP sensor will not generate a code. The ELD code, once again, is most likely due to a different wiring issue.

A brief explanation of the P1689 code and definition of P1689 is given below.

What Does P1689 Code Mean On Dodge Cummins?

Powertrain Code is abbreviated as P. Engine, gearbox, and emissions systems are all involved in the problem.

  • MFG (Manufacturer Specific) is represented by the number 1.
  • BBV Sensor Circuit Low Voltage is represented by the number 6.
  • BBV Sensor Circuit Low Voltage is represented by the number 8.
  • Transmission is represented by the number 9.

MFG stands for Manufacturer. Specific codes feature a ‘1’ as the second number to indicate that they are specific to a particular car make or model.

Vehicle manufacturers thought these specific codes were required to offer extra diagnostic data beyond the standard class of similar OBD II codes for all types of defects, not only emissions-related errors.

Symptoms of Getting the P1689 Code on a Dodge Cummins

If this reaction arises, there are a few signs that occur like – the first is that the engine light comes on. The second is that when the gas pedal is pushed, the car does not accelerate.

Another sign is when the accelerator is pressed, the engine stalls. While diagnosing the problem, you may notice a few more symptoms. The first is a drop in gas mileage efficiency.

Low gas pressure is another sign that the engine isn’t getting what it needs. As the part fails, you may hear rattling noises from the back of the vehicle. A possible symptom is an illuminated engine light or a service engine shortly warning light.

The Causing Factors of the Error Code P1689

The several causing factors of the P1689 code is given below:

  1. The check engine light comes on when the ECM senses that the gasoline injector isn’t operating properly. A defective FPCM might have caused the problem.

  2. It might have also started with an open harness or an FPCM short. A faulty electrical circuit connection in the pump controller module might be the source of the problem.

  3. The automobile will not function correctly if the part fails since it helps power the engine. The engine may stall. Despite pressing the accelerator pedal, it may not accelerate.

  4. The problem might potentially occur if the Powertrain Control Module’s memory or code is corrupted. The response might also be triggered by a hardware mistake in the PCM.

How Serious Is Code P1689 on Dodge Cummins?

The problem is severe since it impairs the engine’s performance. The Fuel Pump Control Module (FPCM) is constantly monitored by the ECM. It’s also possible that the reaction is due to a fault with the Powertrain Control Module, which is a major problem.

Repairing both control modules might be costly. These critical modules are required for the engine to work correctly.

How to Solve P1689 Error Code on Dodge Cummins?

Depending on the kind of engine, there are two primary forms of cylinder deactivation currently in use. The pushrod arrangement that employs solenoids to change the oil pressure provided to the lifters is coded P1689.

The steps to solve this problem are given below:

Step 1- To find out what the number is, you should utilize a scan tool. Then use the scan tool to look at the freeze frame data a second time. Search for the diagnostic issue key using the scan tool as well.

Step 2- If you obtain a consistent response, you should investigate the engine’s components. It’s easier to tell if connections are rusted with a flashlight.

Step 3- The ECM reader is used to obtain the reading to diagnose the problem. Visually check the wire harness and contacts near the damaged portion after obtaining the response.

Step 4- Then, examine for any components that have been damaged. If connecting pins are corroded, the key response is triggered. If the pins aren’t rusted, look for twisted or broken pins. It’s also possible that certain connecting pins will be pushed out.

Step 5- Examine the filter if the error response persists after examining the connections and pins. You’re searching for a decline in gas pressure. Check for an obstruction in the transferring inlet where the gas is supplied to the engine.

Step 6- Inspect the battery terminals as well to ensure that everything is in working order. You may see oil or gas spitting around the engine if there is difficulty with the component. You could observe droplets splattered throughout the interior of the engine if you open the hood.

How Much Does It Cost To Solve The Error Code P1689?

The labor cost to analyze the P1689 code is one hour. The diagnosing time and labor prices for auto repairs vary by region, vehicle model number, and even engine type.

The parts by themselves will cost between $100 and $250, with labor costing between $75 and $150 to fix the sensor.

Employing a dealership to fix your vehicle will, of course, be more expensive than hiring an individual mechanic. Unless you have substantial automotive repair expertise, you should not attempt replacement yourself in most cases.

Common Mistakes While Solving the P1689 Code

There are a few basic errors to avoid while diagnosing this issue. The engine may require an oil change, which is a regular problem. This has minimal bearing on the setback.

Fuel contamination is another typical misdiagnosis. Some folks incorrectly identify the problem and replace the battery. Unless a connection is broken or rusted, the problem is almost always caused by the battery.

Additional Comments to Consider Regarding the P1689 Code

There is most certainly an issue with the fuel pump when the problem numbers show. This is a potentially costly fix. There are a few actions you should do to maintain your gasoline pump in good operating order.

To begin, you should use high-quality gasoline. Because the fuel pump has to filter many contaminants when you use low-quality gasoline, it wears out. As a result, always follow your manufacturer’s fuel recommendations.

Then you should never drive on low fuel or allow the car to come close to empty. Contaminants accumulate and jam the component while the automobile is running on low gasoline. The gasoline pump eventually fails.

The lifters are unable to lift their partner push rods beneath the valve rocker arms in their compressed form, leading in valves that are unable to be activated and remain closed.


You should clean your gasoline tank regularly. Moisture can seep into the gasoline tank and pump if you keep your car. Sediment builds up in the tank if you don’t drive your car or if you drive it with little gasoline. The tank may corrode and the gasoline pump may fail as a result.

I hope our discussion today gave you all of the knowledge you needed. It was over when it comes to the P1689 code on a Dodge Cummins.

Keep an eye on the code and attempt to fix it as soon as possible. Take into account all of my suggestions and, if required, seek professional aid.

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