Immobilizer System Troubleshooting
Troubleshooting1. Turn the ignition switch ON (II) with a programmed key.
2. Check to see if the immobilizer indicator comes on.
Does the indicator come on?
YES - Go to step 3.
No - Go to step 12.
3. Check the immobilizer indicator operation.
Does the indicator come on for 2 seconds, then go off?
YES - Go to step 4.
No - Go to step 6.
4. Try to crank the engine.
Does the starter motor operate?
YES - Go to step 5.
No - Check the starter motor.
5. Try to start the engine.
Does the engine start?
YES - Check the Status Log in the Immobilizer Info with the HDS.
No - Go to step 30.
6. Check to see if the immobilizer indicator comes on and blinks.
Does the indicator blink?
YES - Go to step 27.
No - Go to step 7.
7. Disconnect the 7P connector from the immobilizer control unit-receiver.
8. Check to see if the immobilizer indicator goes off.
Does the indicator go off?
YES - Substitute a known-good immobilizer control unit-receiver and/or PCM.
No - Go to step 9.
9. Turn the ignition switch OFF.
10. Remove the gauge control module and disconnect its connectors.
11. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 terminal and body ground.
Is there continuity?
YES - Repair a short in the wire.
No - Faulty immobilizer indicator, replace the gauge control module.
12. Try to start the engine.
Does the engine start?
YES - Go to step 13.
No - Go to step 19.
13. Turn the ignition switch OFF.
14. Disconnect the 7P connector from the immobilizer control unit-receiver.
15. Check for voltage between the immobilizer control unit-receiver 7P connector No. 7 (+B) terminal and body ground.
Is there battery voltage?
YES - Go to step 16.
No - Faulty No. 7 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and under-dash fuse/relay box.
16. Using a jumper wire, connect the immobilizer control unit-receiver No. 5 terminal to ground.
Does the indicator come on?
YES - Replace the immobilizer control unit-receiver.
No - Go to step 17.
17. Remove the gauge control module and disconnect its 20P connector.
18. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 terminal and gauge control module connector C (20P) No. 18 terminal.
Is there continuity?
YES - Faulty immobilizer indicator, replace the gauge control module.
No - Repair an open in the wire.
19. Turn the ignition switch OFF.
20. Disconnect the 7P connector from the immobilizer control unit-receiver.
21. Turn the ignition switch ON (II).
22. Check for voltage between the immobilizer control unit-receiver 7P connector No. 6 terminal and body ground.
Is there battery voltage?
YES - Go to step 23.
No - Faulty No. 19 (15 A) fuse in the under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and under-dash fuse/relay box.
23. Check for voltage between the immobilizer control unit-receiver 7P connector No. 1 and No. 6 terminals.
Is there battery voltage?
YES - Substitute a known-good immobilizer control unit-receiver control and recheck.
No - Go to step 24.
24. Turn the ignition switch OFF.
25. Disconnect the PCM connector A (44P).
26. Check for continuity between the immobilizer control unit-receiver 7P connector No. 1 terminal and PCM connector A (44P) No. 23 terminal.
Is there continuity?
YES - Check for poor connection atG101. If OK, substitute a known-good immobilizer control unit-receiver and recheck.
No - Repair an open in the wire.
27. Turn the ignition switch OFF.
28. Connect the HDS to the data link connector.
29. Turn the ignition switch ON (II).
30. Look at the System Check in the Immobilizer Info with the HDS.
Is the immobilizer system normal?
YES - Go back to step 1.
No - Go to step 31.
31. Verify the System Check display on the HDS.
- Harness short from the PCM to the immobilizer unit. (S-net line short)
- The communication was not good between the PCM and the immobilizer unit by the battery voltage low.
- The communication was not good between the immobilizer unit and the PCM by influence of some noise.
- Immobilizer unit failure
- PCM failure
Does the HDS display any of the preceding information?
YES - Go to step 32.
No - Go to step 36.
32. Turn the ignition switch OFF.
33. Disconnect the 7P connector from the immobilizer control unit-receiver.
34. Disconnect the PCM connector A (44P).
35. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 (IMOCD) terminal and body ground.
Is there continuity?
YES - Repair a short in the wire.
No - Substitute a known-good immobilizer control unit-receiver and/or PCM.
36. Verify the System Check display on the HDS.
- Blown fuse
- Harness open from the PCM and the immobilizer unit.
- The communication was not good between the PCM and the immobilizer unit by battery voltage low.
- The communication was not good between the immobilizer unit and the PCM by influence of some noise.
- Immobilizer unit failure
- PCM failure
Does the HDS display any of the preceding information?
YES - Go to step 37.
No - Check the Possible Failures shown on the System Check display.
37. Turn the ignition switch OFF.
38. Disconnect the 7P connector from the immobilizer control unit-receiver.
39. Disconnect the PCM connector A (44P).
40. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 (IMOCD) terminal and PCM connector A (44P) No. 36 terminal.
Is there continuity?
YES - Substitute a known-good immobilizer control unit-receiver and recheck the system. If the immobilizer control unit-receiver is OK, substitute a known-good PCM and recheck.
No - Repair an open in the wire.