Key Interlock System Circuit Troubleshooting
Key Interlock System Circuit Troubleshooting1. Check the DTC P0706, P0706, and P0812 is indicated.
Does the HDS indicate code P0705, P0706, and P0812?
YES - Perform the troubleshooting for the indicated code(s).
NO - Go to step 2.
2. Turn the ignition switch OFF.
3. Remove the key interlock relay, and check for continuity between these terminals:
- No. 3 and No. 5
- No. 1 and No. 4
- No. 1 and No. 2 while connecting battery voltage to terminals No. 3 and No. 5, and also check for no continuity between terminals No. 1 and No. 4.
Does the key interlock relay test OK?
YES - Go to step 4.
NO - Replace the key interlock relay.
4. Turn the ignition switch to the ACC (1) position.
5. Measure the voltage between the key interlock relay connector terminal No. 1 and body ground.
Is there battery voltage?
YES - Go to step 6.
NO - Check for blown No. 8 fuse in the under-dash fuse/relay box. If the fuse is OK, repair open in the wire between the key interlock relay connector terminal No. 1 and the under-dash fuse/relay box.
6. Measure the voltage between the key interlock relay connector terminal No. 5 and body ground.
Is there battery voltage?
YES - Go to step 7.
NO - Check for blown No. 8 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is OK, repair open in the wire between the key interlock relay connector terminal No. 5 and the under-dash fuse/relay box.
7. Measure the voltage between the key interlock relay connector terminal No. 3 and No. 5.
Is there battery voltage?
YES - Go to step 8.
NO - Repair open in the wire between the key interlock relay connector terminal No. 3 and ground (G101), or repair poor ground (G101).
8. Turn the ignition switch OFF.
9. Disconnect steering lock assembly connector (6P).
10. Turn the ignition key to ACC (1) or ON (II).
11. Connect the steering lock assembly connector (6P) terminal No. 4 to the battery positive terminal, and connect the battery negative terminal to terminal No. 3.
12. Check the key interlock solenoid operation. A clicking sound should be heard while the ignition key is in ACC (1) and ON (II), and you should not be able to turn it to OFF (0) position.
Does the key interlock solenoid operate properly?
YES - Go to step 13.
NO - Faulty key interlock solenoid/switch. Replace the ignition key cylinder/steering lock assembly.
13. Check for continuity between the steering lock assembly connector (6P) terminal No. 3 and ground.
Is there continuity?
YES - Go to step 14.
NO - Repair open in the wire between the steering lock assembly connector (6P) terminal No. 3 and ground (G402), or repair poor ground (G402).
14. Turn the ignition switch ON (II), and measure the voltage between the steering lock assembly connector (6P) terminal No. 3 and No. 4.
Is there voltage?
YES - Go to step 15.
NO - Check for open or short in the wire between the steering lock assembly connector (6P) terminal No. 4 and the multiplex control unit. If the wire is OK, check for loose terminal fit in the multiplex control unit connectors. If necessary, substitute a known-good multiplex control unit and recheck.
15. Disconnect the transmission gear selection switch/ park pin switch connector.
16. Check for continuity between the transmission gear selection switch/park pin switch connector terminal No. 1 and No. 4 while you move the shift lever in and out of the P position.
Is there no continuity with the shift lever in the P position, and continuity with the shift lever in any position other than P?
YES - Repair open or short in the wires between the transmission gear selection switch/park pin switch connector and the multiplex control unit. If wires are OK, check for loose terminal fit in the multiplex control unit connectors. If necessary, substitute a known-good multiplex control unit and recheck.
NO - inspect the park pin linkage. If the linkage is OK, replace the park pin switch.