Test E: Change Engine Oil Message Inoperative

If vehicle has been checked for DTCs, go to next step. If vehicle has not been checked for DTCs, check for DTCs. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
If speedometer operates, go to next step. If speedometer does not operate, diagnose speedometer concern. See TEST C: SPEEDOMETER GAUGE &/OR ODOMETER INACCURATE/INOPERATIVE .
Disconnect PCM 80-pin harness connector C2. PCM is located in right front corner of engine compartment. Turn ignition switch to RUN position. If CHANGE OIL SOON indicator illuminates, go to next step. If CHANGE OIL SOON indicator does not illuminate, go to step 5 .
Disconnect instrument cluster 32-pin harness connector. Check for continuity between ground and PCM harness connector C2 terminal No. 36 (Gray wire). If continuity exists, repair as necessary. If continuity does not exist, replace instrument cluster. If concern still exists after repair, go to next step. If concern does not exist, system is okay.
Using a fused jumper wire (3-amp), connect ground to PCM harness connector C2 terminal No. 36 (Gray wire). Turn ignition switch to RUN position. If CHANGE OIL SOON indicator does not illuminate, go to next step. If CHANGE OIL SOON indicator illuminates, perform powertrain diagnostic system check. See appropriate BODY CONTROL MODULES article.
Measure resistance in Gray between instrument cluster harness connector terminal C11 and PCM harness connector C2 terminal No. 36. If resistance is 2 ohms or more, go to next step. If resistance is less than 2 ohms, go to step 8 .
Repair open in Gray wire between instrument cluster and PCM. If concern still exists, go to next step. If concern does not exist, system is okay.
Inspect CHANGE OIL SOON indicator and connection. If CHANGE OIL SOON indicator and connection are okay, replace instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION.