Electrical Components
Verify customer complaint. Visually inspect the following electrical components of the shift lock system:
- Fuses No. 10 or 11 (10-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 (10-Amp)
Remove and check fuse No. 11 (10-amp), located in central junction box. See WIRING DIAGRAMS . If fuse is blown, go to next step. If fuse is okay, go to step 4. - Check VPWR Circuit (Light Green/Red Wire) To BPP Switch For Short To Ground
Ensure fuse No. 11 (10-amp) is removed from central junction box. Disconnect BPP switch harness connector. 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) To BPP Switch For Open
Using DVOM, measure resistance between fuse No. 11 output terminal and BPP switch harness connector terminal No. 1 (Light Green/Red wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, 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
Apply brake pedal and hold. Using DVOM, measure resistance between both BPP switch harness connector terminals. Resistance should be more than 10 k/ohms without brake pedal applied and less than 5 ohms with brake pedal applied. If switch resistance is as specified, go to next step. If switch resistance is not as specified, replace BPP switch and retest system. - Check VPWR Circuit (Red/Light Green Wire) To Shift Lock Actuator 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 (Red/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 Red/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 (Red/Light Green Wire) To Shift Lock Actuator For Open
Using DVOM, measure resistance of Red/Light Green wire between BPP switch harness connector terminal No. 2 and shift lock actuator harness connector terminal No. 1. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Red/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 (Red/Black Wire) To Shift Lock Actuator For Voltage
Turn ignition switch to ON position. Using DVOM, measure voltage between chassis ground and shift lock actuator harness connector terminal No. 3 (Red/Black wire). If battery voltage is not present, go to next step. If battery voltage is present, go to step 12. - Check Fuse No. 10 (10-Amp)
Turn ignition switch to OFF position. Remove and check fuse No. 10 (10-amp), located in central junction box. See WIRING DIAGRAMS . If fuse is blown, go to next step. If fuse is okay, go to step 11. - Check VPWR Circuit (Red/Black Wire) To Shift Lock Actuator For Short To Ground
Using DVOM, measure resistance between chassis ground and shift lock actuator connector terminal No. 3 (Red/Black 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 Red/Black wire between fuse No. 10 and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check VPWR Circuit (Red/Black Wire) To Shift Lock Actuator For Open
Using DVOM, measure resistance of Red/Black wire between fuse No. 10 output terminal and shift lock actuator harness connector terminal No. 3. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Red/Black wire between fuse No. 10 and shift lock actuator connector. See WIRING DIAGRAMS . Reconnect all connectors and retest system. - Check Ground Circuit (Black Wire) 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.