What it means
The voltage on the secondary side of the fuel pump circuit is higher than expected. Typical of a stuck relay or short to supply voltage that keeps the pump powered when it should be off.
At a glance
- Usually lights the check-engine light
How it works
The fuel pump secondary circuit carries power to the pump, while the control module checks whether that circuit is powered when commanded on or off. P0232 sets when the monitored voltage is higher than expected, which can happen if the pump relay stays closed or wiring feeds the circuit from another power source.
Common causes
Most likely first.
- Pump relay stuck closed
- Wire shorted to supply voltage
- Connector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
How to diagnose it
- Use a scan tool to record freeze-frame data and check whether the fault is present with the ignition on and the engine off, when the pump should not be running.
- Inspect the fuel-pump relay, its socket, and the secondary-circuit wiring for heat damage, corrosion, loose pins, or contact with a power wire.
- With the vehicle’s wiring diagram, check whether the pump remains powered after the module commands it off and whether the relay contacts are stuck closed.
- With the circuit safely isolated, test the secondary wiring for an unintended connection to battery supply and compare results with the manufacturer’s specification.
- If the relay, wiring, and connections test correctly, check the module’s control of the relay and circuit against the manufacturer’s diagnostic procedure.
Common fixes
- Repair a loose or corroded fuel-pump relay connection.
- Replace a relay that remains closed when it should switch off.
- Repair wiring shorted to a power supply.
- Replace a failed control module only after its wiring and outputs have been verified.
Can I keep driving?
Avoid driving if the engine stalls, is difficult to start, or loses power under load; arrange a safe stop if it cuts out in traffic. A pump that stays powered when it should be off can also drain the battery or create a safety concern, so have the fault checked promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.