Technical Description of OBD-II Trouble Code
The voltage in the Fuel Pump Secondary (Feedback) Circuit is too high.
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code that applies to vehicles equipped with OBD-II. Although it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
The fuel pump is powered by the fuel pump relay. When the powertrain control module (PCM) activates the fuel pump relay, it supplies voltage to the fuel pump, pressurizing the fuel system. Some vehicles have a feedback circuit on the fuel pump supply circuit. This circuit is spliced into the voltage feed to the fuel pump and is usually located near the PCM.
The PCM monitors this feedback circuit to ensure that the fuel pump is receiving the correct voltage. When it activates the fuel pump relay, it expects to see battery voltage on the feedback circuit. If the PCM detects an unexpectedly high voltage when the fuel pump is not activated, it may set the P0232 code.
Symptoms
Symptoms of a P0232 DTC may include:
Causes
Potential causes of a P0232 code include:
Possible Solutions
If you hear the fuel pump running continuously, even with the ignition off, you may be able to skip some of the following checks. Start by turning the key on with the engine off (KOEO) and waiting for a few seconds. This allows the PCM to complete its fuel pump pre-cycle. Then, if you have a scan tool, observe the FP VOLTAGE FEEDBACK reading in the datastream. This reading indicates the voltage the fuel pump is receiving.
If you do not have access to a scan tool, you can use a voltmeter to measure the fuel pump voltage at the fuel tank. If your reading shows any voltage present at the fuel pump with KOEO (or if you can hear the pump running), remove the fuel pump relay. If the voltage remains or the fuel pump continues to run, there may be a short to voltage on the fuel pump voltage supply circuit or feedback circuit. Repair as necessary. If the voltage disappears (or the pump stops running) with the fuel pump relay removed, try replacing the relay with a spare one. If the voltage disappears after replacing the relay, the relay was faulty due to a short. However, if the voltage is still present, suspect that the PCM fuel pump relay control circuit is shorted to ground.
To check for a short to ground on the PCM fuel pump relay control (ground driver) circuit, remove the fuel pump relay and measure the continuity between a good ground and the PCM fuel pump relay control. There should be no continuity to ground with KOEO (after the fuel pump pre-cycle is completed). If there is continuity to ground, the wire is shorted. Find and repair the short as necessary. If you cannot find a physical short, you may need to cut the fuel pump relay control wire close to the PCM connector for easier repair and check for continuity to ground with KOEO coming out of the PCM. If there is no continuity, the wire is shorted in the harness. However, if continuity exists, the driver may be internally shorted to ground and the PCM may need to be replaced.
