The oil pressure sensor is threaded into the engine block (see location illustrations). Low oil pressure (less than 10 psi) will close the switch, creating a circuit that includes the warning light. The light will go on when the switch is closed.
Disconnect the harness wire(s) from the sensor. Connect a jumper wire from the harness wire to ground on the engine (if single wire) or across the two harness wires.
Turn the ignition switch
. The low oil pressure warning light should go ON. Disconnect the jumper. The light should go
. If the lamp does not light when the circuit is completed, suspect a burned out bulb or wiring problem.
With the engine off and oil pressure "zero", check for continuity across the switch body. On single-terminal switches, check continuity between the switch terminal and ground on the switch body or engine block. On two-terminal switches, check for continuity between the two terminals. In either case, there should be continuity. If not, replace the switch.
Fig. Oil pressure sensor location near distributor-3.9L, 5.2L, 5.9L (gas engine)
Fig. Oil pressure sensor location-4.7L engine
Fig. Oil pressure sensor location-8.0L
Fig. Oil pressure sensor location-diesel
REMOVAL & INSTALLATION
Disconnect the battery negative cable.
Disconnect the wiring from the oil pressure sensor.
Unscrew the old sensor.
Coat the threads of the new sensor with Teflon® tape or an oil-resistant sealer.
Tighten the sensor to 11-15 ft lbs. (15-20 Nm).
Reconnect wiring. Start the engine and check operation. Check for leaks.