Code 54, Fuel Pump Circuit
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1995 GMC Vandura, 1995 GMC Rally, 1995 GMC Pickup, 1995 Chevrolet Sportvan, and 1995 Chevrolet Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The status of fuel pump signal is monitored by control module and is used to compensate fuel delivery based on system voltage. Signal is also used to store Code 54 if fuel pump relay is defective or if relay voltage is lost after engine is running. Voltage should be present at fuel pump signal terminal of control module the first 2 seconds after ignition is turned on and anytime reference (RPM) pulses are being received by control module.