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Home >> Jeep >> 2025 >> Grand Cherokee Altitude, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 91 (2.0L - DTCS U0101 To U0168) >> DTC Troubleshooting >> U0109 Lost Communication With Fuel Pump Control Module >> Possible Causes

Possible Causes

WARNING: This page is about a different car, the 2025 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
Possible Causes
FUEL PUMP RELAY OUTPUT CIRCUIT OPEN/HIGH RESISTANCE
FPCM FEEDBACK RETURN CIRCUIT SHORTED TO GROUND
FPCM FEEDBACK RETURN CIRCUIT SHORTED TO VOLTAGE
FPCM FEEDBACK RETURN CIRCUIT OPEN/HIGH RESISTANCE
FUEL PUMP ASSEMBLY PWM CONTROL CIRCUIT SHORTED TO GROUND
FPCM GROUND CIRCUIT OPEN/HIGH RESISTANCE
FUEL PUMP CONTROL MODULE (FPCM)
POWERTRAIN CONTROL MODULE (PCM)

Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding. Refer to:  2.0L - PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE  .