Possible Causes

Purpose of the DTC
To detect a stuck low failure on the signal line between the engine control module and the fuel pump driver module
Electrical Cause
Yes
Mechanical Cause
No
Control Module Signal Name
EFPC - Output PWM signal from engine control module
PWM - Input PWM signal to fuel pump driver module
Monitor Description
When the fuel pump is being controlled by the engine control module, an internal hardware check is performed on the status of the output pin. If the engine control module is requesting fuel pump duty within the range 10%-90% it is possible to detect a high/low circuit failure within 500ms
Prioritized List of Possible Causes
The engine control module has detected a ground measurement for a period longer than expected or has detected a ground measurement when another value was expected
Output PWM signal from engine control module to fuel pump driver module circuit short circuit to ground, high resistance
Connector is disconnected, connector pin is backed out, connector pin corrosion
Fuel pump driver module failure
Engine control module failure