DTC U0109 - Lost Communication With Fuel Pump Control Module A

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U0109 - LOST COMMUNICATION WITH FUEL PUMP CONTROL MODULE A

Description:	The 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. This DTC sets when the PCM is still not detecting a duty cycled signal on the FPM circuit after a calibrated amount of time.
Possible Causes:	FPM circuit open or short to ground FPM circuit short to voltage VPWR fuel circuit open GND circuit open Damaged inertia fuel shutoff (IFS) switch (if equipped) Damaged fuel pump control module relay
Diagnostic Aids:	Check if the inertia fuel shutoff (IFS) switch is tripped.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST KC .