Electrical Components
Verify customer complaint. Visually inspect the following electrical components of the shift lock system:
- Fuse No. 6 (10-amp) or fuse No. 11 (15-amp).
- Loose or damaged connections.
- Brake Pedal Position (BPP) switch connections.
- Wiring harness.
NOTE:
See appropriate wiring diagram to diagnose electrical circuits and identify fuses and circuit numbers. See WIRING DIAGRAMS .
- Check Brakelight Operation
Apply brake pedal. If brakelights illuminate, go to step 7. If brakelights do not illuminate, go to next step. - Check Fuse No. 11 (15-Amp)
Check fuse No. 11 (15-amp), in central junction box. See WIRING DIAGRAMS . If fuse is okay, go to step 4. If fuse is blown, go to next step. - Check VPWR Circuit (Light Green/Red Wire) To BPP Switch For Short To Ground
Turn ignition switch to OFF position. Disconnect BPP switch harness connector. Ensure fuse No. 11 (15-amp) is still removed from central junction box. Using DVOM, measure resistance between chassis ground and BPP switch harness connector terminal No. 1 (Light Green/Red wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Light Green/Red wire between fuse No. 11 and BPP switch. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check VPWR Circuit (Light Green/Red Wire) For Open
Using DVOM, measure resistance between fuse No. 11 output side terminal and BPP switch harness connector terminal No. 1 (Light Green/Red wire). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Light Green/Red wire between fuse No. 11 and BPP switch. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check BPP Switch
Disconnect BPP switch harness connector. Using DVOM, measure resistance between BPP switch terminals while open (OFF) and closed (ON). Resistance should be more than 10 k/ohms while open (OFF) and 5 ohms or less while closed (ON). If resistance is as specified, go to next step. If resistance is not as specified, replace BPP switch. Reconnect all connectors and retest system. - Check VPWR Circuit (Light Green Wire) From BPP Switch For Short To Ground
Disconnect shift lock actuator 3-pin connector. Using DVOM, measure resistance between chassis ground and shift lock actuator harness connector terminal No. 1 (Light Green wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Light Green wire between BPP switch harness connector and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check VPWR Circuit (Light Green Wire) For Open
Using DVOM, measure resistance between BPP switch harness connector terminal No. 2 (Light/Green wire) and shift lock actuator harness connector terminal No. 1 (Light/Green wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Light Green wire between BPP switch harness connector and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check VPWR Circuit (Purple/Orange Wire) To Shift Interlock Actuator
Turn ignition switch to ON position. Using DVOM, measure voltage between chassis ground and shift lock actuator harness connector terminal No. 3 (Purple/Orange wire). If battery voltage is not present, go to next step. If battery voltage is present, go to step 12. - Check Fuse No. 6 (10-Amp)
Turn ignition switch to OFF position. Remove and check fuse No. 6 (10-amp). See WIRING DIAGRAMS . If fuse is blown, go to next step. If fuse is okay, go to step 11. - Check VPWR Circuit (Purple/Orange Wire) For Short To Ground
Using DVOM, measure resistance between chassis ground and shift lock actuator harness connector terminal No. 3 (Purple/Orange wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair open in Purple/Orange wire between fuse No. 6 and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check VPWR Circuit (Purple/Orange Wire) For Open
Using DVOM, measure resistance between fuse No. 6 output terminal and shift lock actuator harness connector terminal No. 3 (Purple/Orange wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Purple/Orange wire between fuse No. 6 and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check Ground Circuit (Black Wire) To Shift Lock Actuator For Open
Using DVOM, measure resistance between chassis ground and shift lock actuator harness connector terminal No. 2 (Black wire). If resistance is 5 ohms or less, replace shift lock actuator. Reconnect all connectors and retest system. If resistance is more than 5 ohms, repair open in Black wire between shift lock actuator connector and ground. See WIRING DIAGRAMS . Reconnect all connectors and retest system.
NOTE:
VPWR circuit wire color may also be Violet/Orange.