DTC 54

Code 54 Chart:

Wiring Diagram For Fuel Relay Circuit.:

CIRCUIT DESCRIPTION:

When the ignition switch is turned "ON," the ECM will energize the fuel pump relay and the in-tank fuel pump. It will remain "ON" as long as the engine is cranking or running, and the ECM is receiving ignition reference pulses. If there are no reference pulses, the ECM will shut "OFF" the fuel pump within 2 seconds after the ignition is "ON" or engine stops. Should the fuel pump relay or the 12.0 volts used to drive the relay fail, the fuel pump will be controlled through the oil pressure switch back-up circuit. A Code 54 will set if the ECM does not sense the 12.0 volt signal at terminal "B2" during the 2 seconds that the ECM is energizing the fuel pump relay.


DIAGNOSTIC AIDS:

An inoperative fuel pump relay can result in an extended cranking time, particularly if the engine is cold or engine oil pressure is low. If the oil level is low, oil pressure will take a while to build-up in order to energize the fuel pump. The oil pressure switch closes (energizes the fuel pump) at approximately 28kPa (4.0 psi).