Test Ab: Speed Control Indicator Is Always/Never On
NOTE:
Tests skip from TEST Z to TEST AB. No tests have been omitted.
- Test drive vehicle and operate speed (cruise) control system. If speed control system operates correctly, but CRUISE indicator does not illuminate, go to next step. If speed control system operates correctly, but CRUISE indicator is illuminated all the time, go to step 4. If speed control system does not operate correctly, repair speed control system problem. See appropriate CRUISE CONTROL SYSTEMS article.
- Turn ignition switch to LOCK position. Disconnect Powertrain Control Module (PCM) 104-pin harness connector C1027 (diesel) or speed servo 10-pin harness connector C1067 (gasoline). PCM is located on left side of firewall. Speed control servo is located in right side of engine compartment, near starter motor relay. On diesel engines, connect a 10-amp fused jumper wire between ground and PCM 104-pin harness connector C1027 terminal No. 45 (Orange/Light Blue wire). See Figure. On gasoline engines, connect a 10-amp fused jumper wire between ground and speed control servo 10-pin harness connector C1067 terminal No. 1 (Orange/Light Blue wire). See Fig 1. If CRUISE indicator does not illuminate, go to next step. If CRUISE indicator illuminates on diesel engines, replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. Retest system operation If CRUISE indicator illuminates on gasoline engines, replace speed control servo. See appropriate CRUISE CONTROL SYSTEMS article. Retest system operation.
- Turn ignition switch to LOCK position. Remove instrument cluster to gain access to instrument cluster harness connectors. See REMOVAL & INSTALLATION . Disconnect instrument cluster 16-pin harness connector C250B. On diesel engines, measure resistance of Orange/Light Blue wire between instrument cluster 16-pin harness connector C250B terminal No. 4 and PCM 104-pin harness connector C1027 terminal No. 45. See Figure and Figure . On gasoline engines, measure resistance of Orange/Light Blue wire between instrument cluster 16-pin harness connector C250B terminal No. 4 and speed control servo 10-pin harness connector C1067 terminal No. 1. See Figure and Fig 1 . If resistance is less than 5 ohms, replace instrument cluster. Retest system operation. If resistance is 5 ohms or more, repair open in Orange/Light Blue wire between instrument cluster and PCM (diesel) or speed control servo (gasoline). See WIRING DIAGRAMS . Retest system operation.
- Turn ignition switch to LOCK position. Disconnect speed control servo 10-pin harness connector C1067 (gasoline) or PCM 104-pin harness connector C1027 (diesel). If CRUISE indicator illuminates, go to next step. If CRUISE indicator does not illuminate on diesel engines, replace PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. Retest system operation. If CRUISE indicator does not illuminate on gasoline engines, replace speed control servo. See appropriate CRUISE CONTROL SYSTEMS article. Retest system operation.
- Turn ignition switch to LOCK position. Disconnect instrument cluster 16-pin harness connector C250B. See Figure. Measure resistance between ground and instrument cluster 16-pin harness connector C250B terminal No. 4 (Orange/Light Blue wire). If resistance is more than 10 k/ohms, replace instrument cluster. See REMOVAL & INSTALLATION . Retest system operation. If resistance is 10 k/ohms or less, repair short to ground in Orange/Light Blue wire between PCM (diesel) or speed control servo (gasoline). See WIRING DIAGRAMS . Retest system operation.