Diagnostic Aids
Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:
- Wiring Harness Circuits (B+, GND & VPWR To Fuel Pump Relay; FP, FPM, FP PWR, FP RTN & FPDM PWR). See Fig 1-Fig 5 .
- Faulty Inertia Fuel Shutoff (IFS) Switch
- Faulty Fuel Pump Driver Module (FPDM)
- Faulty Power Supply Relay Inside Constant Control Relay Module (CCRM)
- Faulty Powertrain Control Module (PCM)
Fig 2: Identifying Fuel Pump Driver Module Circuits & Connector Terminals (Focus, Crown Victoria, Grand Marquis, Sable, Taurus & Town Car)