Key Interlock System Circuit Troubleshooting

Key Interlock System Circuit Troubleshooting
1. Disconnect the key switch connector (7P) from the steering lock assembly.





2. Connect the No. 7 terminal of the key switch connector to the battery positive terminal, and connect the No. 5 terminal to the battery negative terminal.
3. Turn the ignition switch to ACC (1), then push the ignition key.
4. Check the key interlock solenoid operation. A clicking sound should be heard while pushing the ignition key, and you should not be able to turn it to the OFF position.
Does the key interlock solenoid operate properly?
YES - Go to step 5.
NO - Faulty key interlock solenoid/switch. Replace the ignition key cylinder/steering lock assembly.





5. Measure the voltage between the No. 7 terminal and body ground.
Is there battery voltage?
YES - Go to step 6.
NO - Check for a blown No. 47 (20A) fuse in the under-hood fuse/relay box. If the fuse is OK, repair open or short in the wire between the No. 7 terminal of the key switch connector and underhood fuse/relay box.
6. Disconnect the switch assembly connector (6P) on the shift lever.





7. With the shift lever in Park and pushed to the right, check for continuity between the No. 4 and No. 2 terminals of the switch assembly connector (6P).
Is there continuity ?
YES - Go to step 8.
NO - Repair open in the wires between the park pin switch and the switch assembly connector (6P). If the wires are OK, remove the shift lever assembly, and replace the shift lever detent bracket assembly.





8. Check for continuity between the No. 4 terminal of the switch assembly connector (6P) and the No. 5 terminal of the key switch connector.
Is there continuity ?
YES - Go to step 9.
NO - Repair open in the wire between No. 4 terminal of the switch assembly connector (6P) and the No. 5 terminal of the key switch connector.





9. Check for continuity between the No. 2 terminal of the switch assembly connector (6P) and body ground.
Is there continuity ?
YES - Check for loose terminal pin fit in the key switch connector and switch assembly connector (6P). If necessary, substitute a known-good steering lock assembly.
NO - Repair open in the wire between the No. 2 terminal of the switch assembly connector (6P) and ground (G401), or repair poor ground (G401).