Test Z: Low Engine Oil Level Indicator Always On

If instrument cluster diagnostic system check has been performed, go to next step. If instrument cluster diagnostic system check has not been performed, perform INSTRUMENT CLUSTER DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM.
Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, near steering column. Turn ignition switch to RUN position. Using scan tool, observe engine oil level switch parameter in Powertrain Control Module (PCM) engine 3 data list. If engine oil level switch parameter displays as OK, go to next step. If engine oil level switch parameter does not display as OK, go to step 4 .
If low engine oil indicator is illuminated, go to step 11 . If low engine oil indicator is not illuminated, inspect for intermittents. See TROUBLE SHOOTING .
Turn ignition switch to OFF position. Disconnect engine oil level switch harness connector. Connect a 3-amp fused jumper wire between ground and engine oil level switch harness connector terminal "A" (Brown wire). Turn ignition switch to RUN position. Using scan tool, observe engine oil level switch parameter. If engine oil level switch parameter does not display OK, go to next step. If engine oil level switch parameter displays OK, go to step 6 .
Inspect Brown wire for an open or high resistance between engine oil level switch harness connector terminal "A" and Powertrain Control Module (PCM) harness connector C2 terminal No. 23. If problem does not exist, go to step 8 . If problem exists, repair Brown wire as necessary. After repair, go to step 12 .
Inspect Black wire for an open or high resistance between ground and engine oil level switch harness connector terminal "B". Ground point is located on lower left front corner of engine on transmission case. If problem does not exist, go to next step. If problem exists, repair Black wire as necessary. After repair, go to step 12 .
Inspect engine oil level switch harness connector for poor connections. If problem does not exist, go to step 9 . If problem exists, repair engine oil level switch harness connector as necessary. After repair, go to step 12 .
Inspect PCM harness connector for poor connections. If problem does not exist, go to step 10 . If problem exists, repair PCM harness connector as necessary. After repair, go to step 12 .
Replace engine oil level switch. After repair, go to step 12 .
Replace PCM. Program PCM. See POWERTRAIN CONTROL MODULE under PROGRAMMING. After repair, go to step 12 .
Replace IPC, then go to next step.
Operate system to verify repair. If system is not operating correctly, repeat test beginning at step 2 .