DTC 54

Code Chart 54:

Fuel Pump Relay Circuit:

CIRCUIT DESCRIPTION:
The status of the fuel pump CKT 120 is monitored by the ECM at terminal "GE13" and is used to compensate fuel delivery based on system voltage. This signal is also used to store a diagnostic trouble code, if the fuel pump relay is defective or fuel pump voltage is lost, while the engine is running. There should be about 12 volts on CKT 120 for 2 seconds, after the ignition is turned "ON," or any time references pulses are being received by the ECM.

DIAGNOSTIC AIDS:
DTC 54 will set, if the voltage at terminal "GE13" is less than 4 volts for .4 seconds since the last reference pulse was received. This DTC is designed to detect a faulty relay, causing extended crank time, and the DTC will help the diagnosis of an engine that "CRANKS BUT WILL NOT RUN."

If a fault is detected during start-up, the MIL (Service Engine Soon) will stay "ON" until the ignition is cycled "OFF." However, if the voltage is detected below 2 volts with the engine running, the light will only remain "ON" while the condition exists.

Check sources of intermittent low system voltage such as loose battery connections, poor generator belt or belt tension or loose generator connections. If OK, - Intermittent Malfunctions