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Home >> Mercury >> 2009 >> Sable Premier, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1255 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P1235: - Fuel Pump Control Out Of Range

DTC P1235: - Fuel Pump Control Out Of Range

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DTC P1235: - FUEL PUMP CONTROL OUT OF RANGE

Description:  This DTC indicates the fuel pump driver module (FPDM) detected an invalid or missing fuel pump (FP) duty cycle signal on the fuel pump control (FPC) circuit from the powertrain control module (PCM). The FPDM sends a message to the PCM through the fuel pump monitor (FPM) circuit, indicating this concern was detected. The PCM sets the DTC when the message is received.
Possible Causes: 
  • FPC circuit open or short
  • Electronic throttle control (ETC) system concern. Check for ETC DTCs
  • Damaged FPDM
  • Damaged PCM
Diagnostic Aids:  The FPDM sends a 25% duty cycle (250 ms on, 750 ms off) through the FPM circuit to the PCM while the concern is being detected by the FPDM. If the concern is no longer detected, the FPDM returns to sending an all OK (50% duty cycle) message to the PCM. For ETC applications, check if ETC DTC P2105 is present. An ETC system concern could cause DTC P1235, and should be diagnosed first.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test KB .