P1237 - Fuel Pump Secondary Circuit Malfunction

2004 Ford Focus ZX5, 2.3 Z, StandardSECTION P1237 - Fuel Pump Secondary Circuit Malfunction
P1237 - FUEL PUMP SECONDARY CIRCUIT MALFUNCTION

Description:  The DTC indicates the FPDM detected a fuel pump secondary circuit fault. The FPDM sends a message to the PCM through the FPM circuit, indicating this failure was detected. The PCM sets the DTC when the message is received.
  • NOTE: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the Rear Electronics Module (REM). Also, the REM does not use an FPM circuit. Diagnostic information is sent on the communication link.
Possible Causes: 
  • Open or shorted FP PWR circuit.
  • Open FP RTN circuit to FPDM.
  • Open or shorted circuit in the fuel pump.
  • Locked fuel pump rotor.
  • Damaged FPDM.
  • For LS6/LS8 and Thunderbird, circuits associated with the Fuel Pump relay.
Diagnostic Aids: 
  • The FPDM sends a 75% duty cycle (750 ms ON, 250 ms OFF) through the FPM circuit to the PCM while the fault is being detected by the FPDM. If the fault is no longer detected, the PCM returns to sending an all OK (50% duty cycle) message to the PCM.
  • The FPDM controls pump speed by supplying a variable ground on the RTN circuit.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to KB: Fuel Pump Driver Module STEP 34
RENDER: 1.0x

NO RELATED

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