DTC C127C GMC

Description

The Powertrain Control Module (PCM) monitors the Fuel Pump Monitor (FPM) circuit for the presence of a duty cycled signal. If the FPM circuit is fixed at a low or high voltage, the PCM begins to increment a counter. The test fails when the PCM is still not detecting a duty cycled signal on the FPM circuit after a calibrated amount of time. Note: Check if the Inertia Fuel Shutoff (IFS) switch is tripped.