Fuel Pump Monitor (FPM) - ERFS

NOTE: The Mustang 5.4L uses two FPDMs to control fuel for the fuel delivery system. The PCM individually monitors both FPDMs through the FPM and FPM2 circuits.

The FPDM communicates diagnostic information to the PCM through the FPM circuit. This information is sent by the FPDM as a duty cycle signal. The three duty cycle signals that may be sent are listed in the following table.

FUEL PUMP DRIVER MODULE DUTY CYCLE SIGNALS

FUEL PUMP DRIVER MODULE DUTY CYCLE SIGNALS REFERENCE

Duty Cycle

Comments

FP_M PID ⁽¹⁾

50%

This duty cycle indicates that the FPDM is functioning normally.

80-125%

25%

This duty cycle indicates that the FPDM either did not receive a fuel pump (FP) duty cycle command from the PCM or did not receive a valid FP duty cycle command from the PCM.

15-60%

75%

This duty cycle indicates that the FPDM detects a concern in the circuits between the fuel pump and FPDM.

250-400%

⁽¹⁾	Some scan tools display the FP_M PID as the duty cycle in column 1. Other scan tools display the FP_M PID as a value shown in the FP_M PID column. This value fluctuates randomly. It is OK for the value to briefly go outside this range, then return.

For additional information, refer to POWERTRAIN CONTROL HARDWARE , FUEL PUMP DRIVER MODULE (FPDM) .