Circuit/System Description

The powertrain control module (PCM) enables the fuel pump relay when the ignition switch is turned ON. The PCM will disable the fuel pump relay within 2 seconds unless the PCM detects ignition reference pulses. The PCM continues to enable the fuel pump relay as long as ignition reference pulses are detected. The PCM disables the fuel pump relay within 2 seconds if ignition reference pulses cease to be detected and the ignition remains ON.

The PCM monitors the voltage on the fuel pump relay control circuit. If the PCM detects an incorrect voltage on the fuel pump relay control circuit, a fuel pump relay control DTC sets.