P0231 - LOW VOLTAGE FUEL PUMP SECONDARY CIRCUIT
Description of DTC code P0231
When the Powertrain Control Module (PCM) activates the fuel pump relay, voltage is supplied to the pump and the fuel system is accelerated. This circuit is spliced into the voltage supply to the fuel pump. The junction is usually located near the PCM.
The PCM often monitors this power circuit to make sure the voltage that is sent to the fuel pump is adequate. As the pump relay is activated, the PCM expects to see the battery voltage in the feedback circuit.
The P0231 OBDII diagnostic code is set when an excessively low voltage is observed or even if no voltage is present.
Symptoms of fault code P0231
- Check Engine light turns on.
- The engine may not start or may stall.
- Inadequate fuel supply.
Causes of OBD2 P0231
Reasons to set the OBD2 code P0231:
- The fuel pump relay may be faulty.
- The fuel pump supply circuit may have been damaged due to worn wiring.
- Perhaps there are incorrectly fitted or faulty connectors.
- The feedback circuit may be shorted.
- Fuel pump fuse shorted to ground.
Possible solutions of the DTC code P0231
To troubleshoot problems related to the P0231 OBDII error code, consider this:
- Check the power supply circuit between the PCM and where the fuel pump supply voltage circuit is spliced. If you find noticeable damage, make some repairs.
- Check the fuel pump fuse.
- Check the resistance between the voltage supply circuit at the pump connector and the ground connection. If there is high or infinite resistance after disconnecting the pump, replace the pump.