Engine Oil Pressure Sensor/Switch Diagnosis

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Engine Controls Schematics: PCM Engine Oil Level and Pressure Inputs:

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) applies battery voltage through a pull up resistor to the engine oil pressure switch circuit. The PCM monitors the applied voltage on the engine oil pressure switch circuit. If the ignition switch is turned On with the engine not running, or the engine oil pressure is less than 35 kPa (5 psi), the engine oil pressure switch grounds the PCM voltage input. The PCM sends the engine oil pressure information via Class 2 serial data to the Instrument Panel Cluster (IPC). The IPC controls the Engine Oil Pressure indicator.

DIAGNOSTIC AIDS
Use the J 35616-A connector test adapter kit for any test that requires probing the PCM harness connectors, electrical center fuse/relay cavities, component terminals or a component harness connector. Using this kit will prevent damage caused by improper probing of connector terminals. If the problem is intermittent, refer to Intermittent Conditions for diagnosis.

Check for the following conditions:
^ Any poor connections - Inspect the PCM and harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connections.
^ A damaged harness - Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the engine oil pressure switch, turn the ignition on, and observe a voltmeter connected between the engine oil pressure switch connector terminals while moving the wiring harnesses related to the engine oil pressure switch circuit. A change in voltage will indicate the location of the fault.