Fuel and air

P0232 — Fuel Pump Secondary Circuit High Voltage

Severity: medium Drive with care, to a shop

What P0232 means

The engine control unit monitors voltage in the secondary control circuit of the fuel pump (the relay or pump module side). P0232 sets when that voltage is higher than expected, for example from a wire shorted to positive, a stuck relay or a failing driver inside the PCM. Normally the voltage follows the commands to turn the pump on and off.

Symptoms

  • Check Engine light on
  • Hard starting or no-start
  • Hesitation or loss of power
  • Engine stalling unexpectedly
  • Fuel pump running with the key off or running erratically

Possible causes

  1. Faulty or stuck fuel pump relay
  2. Short to voltage in the pump control or feedback circuit
  3. Damaged wiring or corroded, burned connectors
  4. Failed fuel pump driver inside the PCM
  5. Internal electrical fault in the fuel pump
  6. Faulty pump control module, if the vehicle has one

How to diagnose

  1. Scan for codes and freeze frame data, and note any other fuel system codes
  2. Inspect the fuel pump relay, fuses and connectors for heat damage or corrosion
  3. Test the relay with a multimeter or swap in a known good one
  4. Inspect the harness from the PCM to the pump, especially where it flexes or rubs the body
  5. With the connector unplugged, check the control circuit for a short to voltage
  6. Measure circuit voltage with the key on and compare with the factory wiring diagram
  7. Check pump current draw and electrical condition
  8. If wiring and relay are good, test the PCM driver output

Common fixes

  • Replace the faulty fuel pump relay
  • Repair the short and fix damaged wiring or connectors
  • Replace the fuel pump if it has an internal electrical fault
  • Repair or replace the PCM if its driver has failed

Questions and answers

What does P0232 mean?

The PCM detected abnormally high voltage in the fuel pump secondary circuit. The usual culprits are the relay, wiring shorted to positive, or the pump itself.

Can I drive with P0232?

Only briefly and carefully, such as to a shop. The engine could stall or refuse to start, so get it repaired soon.

Where should I start diagnosing P0232?

Start with the fuel pump relay, fuse, connectors and wiring. These are the most common and least expensive causes.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.