Fuel Pump Relay Wiring Diagram

Fuel Pump Relay Wiring Diagram (1992-1993 Ford F150, F250, F350 4.9L, 5.0L, 5.8L)

NOTE: The wiring diagram illustrations in this article cover only: 1992-1993 Gasoline 4.9L, 5.0L, and 5.8L F150, F250, and F350 with dual/single gasoline tank.

Fuel Pump Relay Diagnostic/Troubleshooting Notes:

  1. The YEL wire:
    1. Should have 10 to 12 Volts DC with Key On Engine Off (KOEO) or Key On Engine Running (KOER).
  2. The RED wire:
    1. Should have 10 to 12 Volts DC while KOEO or KOER.
    2. This voltage comes from the PCM power relay.
  3. The DK GRN/YEL wire:
    1. Should have 10 to 12 Volts DC for a few seconds when turning the key to the On position.
    2. Should have 10 to 12 Volts when cranking the engine.

Fuel Tank Select Switch Wiring Diagram

Fuel Pump Select Switch Wiring Diagram (1992-1993 Ford F150, F250, F350 4.9L, 5.0L, 5.8L)

Fuel Pump Inertia Switch Diagnostic/Troubleshooting Notes:

  1. The DK GRN/YEL wire:
    1. Should have 10 to 12 Volts DC while cranking the engine.
    2. This power comes from the fuel pump relay.
  2. The RED/YEL wire:
    1. Should have 10 to 12 Volts DC while cranking the engine (if the inertia switch IS NOT tripped).
  3. Inertia Switch (unplugged from its connector):
    1. Continuity should exist between pin that connects to DK GRN/YEL wire and pin that connects to RED/YEL wire (if switch IS NOT tripped).

Fuel Tank Select Switch Diagnostic/Troubleshooting Notes:

  1. The RED/YEL wire should have 10 to 12 Volts DC while cranking the engine.
  2. Front tank selected (switch unplugged from its connector):
    1. Continuity should exist between pin 1 and pin 2.
    2. Continuity should exist between pin 4 and pin 5.
    3. Pin 3 and pin 2 should be ‘open’.
    4. Pin 6 and pin 5 should be ‘open’.
  3. Rear tank selected (switch unplugged from its connector):
    1. Continuity should exist between pin 3 and pin 2.
    2. Continuity should exist between pin 6 and pin 5.
    3. Pin 1 and pin 2 should be ‘open’.
    4. Pin 4 and pin 5 should be ‘open’.

Fuel Pump Unit Wiring Diagram (Dual Tanks)

Fuel Pump Units Wiring Diagram -Dual Tank (1992-1993 Ford F150, F250, F350 4.9L, 5.0L, 5.8L)

NOTE: The above illustration only applies to dual tank equipped Ford pickups. The single tank equipped fuel pump wiring diagram is found in the next page.