Possible causes

– Open Inertia Switch
– Blown Fuel Pump fuse
– Open Fuel Pump Monitor Circuit
– Open Fuel Pump Control Circuit
– Faulty Fuel Pump Relay
– Damaged PCM.

When is the code detected?

The code will be set if a low voltage on the control circuit of the fuel pump relay is detected by the PCM.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0233 MAZDA Description

The powertrain control module (PCM) provides ignition positive voltage to the coil side of the fuel pump relay. When the ignition switch is first turned ON, the PCM energizes the fuel pump relay, which applies power to the fuel pump. The PCM enables the fuel pump relay as long as the engine is cranking or running, and crankshaft reference pulses are received. If no crankshaft reference pulses are received, the PCM de-energizes the fuel pump relay after 2 seconds. The PCM monitors the voltage on the fuel pump relay control circuit.