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U0109 - Lost Communication With Fuel Pump Control Module A - DTC Chart

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U0109 - LOST COMMUNICATION WITH FUEL PUMP CONTROL MODULE A - DTC CHART

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. The test fails 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 .