DTC U0109: Lost Communication With Fuel Pump Control Module

2010 Mercury Mariner Hybrid, AWDSECTION DTC U0109: Lost Communication With Fuel Pump Control Module
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
U0109 - LOST COMMUNICATION WITH FUEL PUMP CONTROL MODULE

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.
Possible Causes: 
  • FPM circuit open or short to ground
  • FPM circuit short to voltage
  • VPWR fuel circuit open
  • PWRGND circuit open
  • Damaged fuel pump control module relay
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST KC .
RENDER: 1.0x

NO RELATED

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