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U0109 MERCURY

U0109 MERCURY - Lost Communication With Fuel Pump Control Module

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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Possible causes

  • Fuel pump monitor circuit open or short to ground
  • Fuel pump monitor circuit short to voltage
  • Damaged Inertia Fuel Shutoff (IFS) switch (if equipped)
  • Damaged fuel pump control module relay

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

U0109 Mercury 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.
OBDII Code U0109 Mercury - Lost Communication With Fuel Pump Control Module  - AutoCodes.com

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U0109 MERCURY Comments

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