Wrangler 4WD L4-150 2.5L VIN P MFI (1998)
Fuel Pump Relay: Description and Operation
Fig. 2 Power Distribution Center (PDC)
FUEL PUMP RELAY-PCM OUTPUT
The Powertrain Control Module (PCM) energizes the electric fuel pump through the fuel pump relay Battery voltage is applied to the fuel pump
relay when the ignition key is ON. The relay is energized when a ground signal is provided by the PCM.
The fuel pump will operate for approximately one second unless the engine is operating or the starter motor is engaged.
The fuel pump relay is located in the Power Distribution Center (PDC) (Fig. 2).
CIRCUIT OPERATION
When the ignition switch is in either the START or RUN positions, it connects circuit A1 from fuse 3 in the Power Distribution Center (PDC) to
circuit A21. Circuit A21 feeds circuit F12 through fuse 11 in the fuse block. Circuit F12 powers the coil side of the fuel pump relay. The
Powertrain Control Module (PCM) provides ground for the relay on circuit K31. Circuit K31 connects to cavity C19 of the PCM.
When the PCM grounds the fuel pump relay, contacts inside the relay close and connect circuit A61 from fuse 16 in the PDC to circuit A141.
Circuit A141 powers the fuel pump motor (part of the in-tank fuel pump module).
