Fuel Pump Driver Module Applications

The fuel pump driver module (FPDM) communicates diagnostic information to the powertrain control module (PCM) through the Fuel Pump Monitor (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

Duty Cycle ⁽¹⁾

On Time (mSec)

Comments

FP_M
PID ⁽²⁾

50%

500

"All OK" output from FPDM. With this input, the PCM can verify that the FPDM is powered and able to communicate on the FPM circuit.

80-125%

25%

250

FPDM did not receive a Fuel Pump (FP) duty cycle command from the PCM, or the duty cycle that was received was invalid (refer to PCM OUTPUTS , FUEL PUMP ).

15-60%

75%

750

The FPDM has detected a fault in the circuits between the fuel pump and FPDM.

250-400%

⁽¹⁾	If a duty cycle meter and breakout box is used, be aware that these values may be reversed depending on the trigger setting of the specific meter (for example, 25% from FPDM may read as 75% on duty cycle meter depending on trigger setting).

⁽²⁾	Some scan tools will display the FP_M PID as the duty cycle in column 1. Other scan tools will display the FP_M PID as a value shown in the FP_M PID column. This value will fluctuate randomly. It is OK for the value to briefly go outside this range, then return.