P0231 Fault Code

Fuel Pump Secondary (Feedback) Circuit Low Voltage

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0231 fault code is related to the fuel pump secondary circuit, which is responsible for providing feedback to the engine control module (ECM) regarding the performance of the fuel pump. This code indicates that the voltage in this circuit is too low, meaning that there may be a problem with the fuel pump itself or with the circuitry that connects it to the ECM.

Possible causes of this fault code include a faulty fuel pump, a damaged or corroded connector in the circuit, or a problem with the wiring that connects the fuel pump to the ECM. In some cases, the ECM itself may be causing the problem.

The solution to this issue will depend on the specific cause of the fault code. It may be necessary to replace the fuel pump, repair or replace damaged wiring or connectors, or replace the ECM. It is recommended to have a professional mechanic diagnose and repair the issue to ensure proper and safe operation of your vehicle.

What are the symptoms of the P0231 code?

Symptoms of P0231 fault code may include:

• Check Engine Light (CEL) is illuminated
• Loss of power while driving
• Engine misfires or stalls
• Rough idling or high idle speed
• Poor acceleration or hesitation
• Fuel economy may decrease
• Difficulty starting the engine
• Fuel gauge reading incorrectly.

What causes the P0231 code?

Causes of P0231 fault code on cars may include:

1. Faulty fuel pump relay
2. Damaged wiring or poor electrical connections in the fuel pump circuit
3. A malfunctioning fuel pump driver module
4. Failed fuel pump
5. Issues with the powertrain control module (PCM)
6. Low battery voltage or a weak alternator

How to fix P0231?

To fix the P0231 fault code on your car, you can do the following:

1. Check the wiring: Check all the wiring related to the fuel pump secondary circuit and look for any damaged or loose wires.

2. Check the fuel pump relay: Check if the fuel pump relay is working properly. A faulty relay can cause low voltage on the feedback circuit.

3. Check the fuel pump control module: Check if the fuel pump control module is working properly. A faulty control module can also cause low voltage on the feedback circuit.

4. Check the fuel pressure sensor: Check if the fuel pressure sensor is working properly. A faulty sensor can cause low voltage on the feedback circuit.

5. Replace the fuel pump: If all the above steps fail to fix the issue, it may be necessary to replace the fuel pump.

It is recommended to take your car to a professional mechanic who can diagnose the issue properly and recommend the best course of action.