Powertrain Controls - ECM/PCM

DTC 54 Fuel Pump Circuit Low Voltage:

Fuel Pump Wiring Diagram:

Circuit Description:

The status of the fuel pump CKT 120 is monitored by the ECM at terminal "A6" 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 reference pulses are being received by the ECM.

DTC 54 will set if the voltage at terminal "A6" is less than 7 volts for 3 second 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 Malfunction Indicator Lamp (MIL) "Service Engine Soon" will stay "ON" until the ignition is cycled "OFF." However, if the voltage is detected below 7 volts with the engine running, the light will only remain "ON" while the condition exists.