Troubleshooting
Immobilizer System Troubleshooting'00-05 models
1. 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 - The immobilizer system is OK at this time.
NO - Go to step 18.
6. Check to see if the immobilizer indicator comes on and blinks.
Does the indicator blink?
YES - Go to step 18.
NO - Go to step 7.
7. Disconnect ECM connector A (32P).
8. Check to see if the immobilizer indicator goes off.
Does the indicator go off?
YES - Substitute a known-good ECM.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Remove the gauge assembly and disconnect its connectors.
11. Check for continuity between ECM connector A (32P) No. 12 (IMOLMP) terminal and body ground.
Is there continuity?
YES - Repair short to ground in the wire.
NO - Faulty immobilizer indicator, replace the immobilizer indicator bulb or gauge assembly.
12. Try to start the engine.
Does the engine start?
YES - Go to step 13.
NO - Substitute a known-good ECM, and recheck.
13. Turn the ignition switch OFF.
14. Disconnect ECM connector A (32P).
15. Measure the voltage between ECM connector A (32P) No. 12 terminal and body ground.
Is there battery voltage?
YES - Go to step 16.
NO - Faulty No. 25 (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 ECM and under-dash fuse/relay box.
16. Remove the gauge assembly and disconnect its connectors.
17. Check for continuity between ECM connector A (32P) No. 12 (IMOLMP) terminal and gauge assembly connector D (16P) No. 15 terminal ('00-03 models) or gauge assembly connector A (22P) No. 4 terminal ('04-05 models).
Is there continuity?
YES - Faulty immobilizer indicator, replace the immobilizer indicator bulb or gauge assembly.
NO - Repair an open in the wire.
18. Turn the ignition switch OFF.
19. Connect the HDS to the data link connector.
20. Turn the ignition switch ON (II).
21. Look at the System Check in the Immobilizer Info with the HDS.
Is the immobilizer system normal?
YES - Go to symptom troubleshooting in the fuel and emissions system.
NO - Go to step 22.
22. Verify the System Check display on the HDS for possible failure.
Does the HDS display IMOCD line failure?
YES - Go to step 23.
NO - Go to step 30.
23. Turn the ignition switch OFF.
24. Check for continuity between the immobilizer receiver unit 5P connector No. 4 terminal and body ground.
Is there continuity?
YES - Go to step 25.
NO - Repair an open in the wire. If the wire is OK, repair G101.
25. Turn the ignition switch OFF.
26. Disconnect the 5P connector from the immobilizer receiver unit.
27. Disconnect ECM connector A (32P).
28. Check for continuity between the immobilizer receiver unit 5P connector No. 2 (IMOCD) terminal and body ground.
Is there continuity?
YES - Repair short to ground in the wire.
NO - Go to step 29.
29. Check for continuity between the immobilizer receiver unit 5P connector No. 2 (IMOCD) terminal and ECM connector A (32P) No. 25 terminal.
Is there continuity?
YES - Substitute a known-good immobilizer receiver unit and/or ECM.
NO - Repair open in the wire.
30. Verify the System Check display on the HDS for the following information:
- IMOEN line failure
Does the HDS display IMOEN line failure?
YES - Go to step 32.
NO - Go to step 31.
31. Measure the voltage between the immobilizer receiver unit 5P connector No. 1 (IG1) terminal and body ground.
Is there battery voltage?
YES - Substitute a known-good immobilizer receiver unit.
NO - Faulty No. 46 (15 A) fuse in the main under-hood fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer receiver unit and main under-hood fuse/relay box.
32. Turn the ignition switch OFF.
33. Disconnect the 5P connector from the immobilizer receiver unit.
34. Disconnect ECM connector A (32P).
35. Check for continuity between the immobilizer receiver unit 5P connector No. 3 (IMOEN) terminal and body ground.
Is there continuity?
YES - Repair a short to ground in the wire.
NO - Go to step 36.
36. Check for continuity between the immobilizer receiver unit 5P connector No. 3 (IMOEN) terminal and ECM connector A (32P) No. 13 terminal.
Is there continuity?
YES - Substitute a known-good immobilizer receiver unit and/or ECM.
NO - Repair open in the wire.
'06-07 models
1 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 28.
6 Check to see if the immobilizer indicator comes on and blinks.
Does the indicator blink?
YES - Go to step 28.
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 ECM.
NO - Go to step 9.
9 Turn the ignition switch OFF.
10 Remove the gauge assembly and disconnect its connectors.
11 Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOLMP) terminal and body ground.
Is there continuity?
YES - Repair short to ground in the wire.
NO - Faulty immobilizer indicator, replace the gauge assembly.
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 Measure the 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. 25 (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 (IMOLMP) terminal to ground.
Does the indicator come on?
YES - Replace the immobilizer control unit-receiver.
NO - Go to step 17.
17 Remove the gauge assembly and disconnect its 22P connector.
18 Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOLMP) terminal and gauge assembly connector A (22P) No. 4 terminal.
Is there continuity?
YES - Faulty immobilizer indicator, replace the immobilizer indicator bulb or gauge assembly.
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 Measure the voltage between the immobilizer control unit-receiver 7P connector No. 6 (IG1) terminal and body ground.
Is there battery voltage?
YES - Go to step 23.
NO - Faulty No. 2 (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 Measure the voltage between the immobilizer control unit-receiver 7P connector No. 1 (LG3) and No. 6 (IG1) 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 Jump the SCS line with the HDS.
26 Disconnect ECM connector E (31P).
27 Check for continuity between the immobilizer control unit-receiver 7P connector No. 1 (LG3) terminal and ECM connector E (31P) No. 3 (LG3) terminal.
Is there continuity?
YES - Check for poor connection at G101. If OK, substitute a known-good immobilizer control unit-receiver and recheck.
NO - Repair open in the wire.
28 Turn the ignition switch OFF.
29 Connect the HDS to the data link connector.
30 Turn the ignition switch ON (II).
31 Look at the System Check in the Immobilizer Info with the HDS.
Is the immobilizer system normal?
YES - Go to symptom troubleshooting in the fuel and emissions system.
NO - Go to step 32.
32 Verify the System Check display on the HDS for the following information:
- Harness short from the ECM to the immobilizer control unit-receiver. (IMOCD (S-Net) line short)
- The communication was not good between the ECM and the immobilizer control unit-receiver by the battery voltage low.
- The communication was not good between the immobilizer control unit-receiver and the ECM by influence of some noise.
- Immobilizer control unit-receiver failure
- ECM failure
Does the HDS display any of the preceding information?
YES - Go to step 33.
NO - Go to step 38.
33 Turn the ignition switch OFF.
34 Disconnect the 7P connector from the immobilizer control unit-receiver.
35 Jump the SCS line with the HDS.
36 Disconnect ECM connector E (31P).
37 Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 IMOCD (S-Net) terminal and body ground.
Is there continuity?
YES - Repair a short to ground in the wire.
NO - Substitute a known-good immobilizer control unit-receiver and/or ECM.
38 Verify the System Check display on the HDS for the following information:
- Blown fuse
- Harness open from the ECM and the immobilizer control unit-receiver.
- The communication was not good between the ECM and the immobilizer unit by battery voltage low.
- The communication was not good between the immobilizer control unit-receiver and the ECM by influence of some noise.
- Immobilizer control unit-receiver failure
- ECM failure
Does the HDS display any of the preceding information?
YES - Go to step 39.
NO - Check the Possible Failures shown on the System Check display
39 Turn the ignition switch OFF.
40 Disconnect the 7P connector from the immobilizer control unit-receiver.
41 Jump the SCS line with the HDS.
42 Disconnect ECM connector E (31P).
43 Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 IMOCD (S-Net) terminal and ECM connector E (31P) No. 27 IMOCD (S-Net) 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 ECM and recheck.
NO - Repair open in the wire.
'08 model
1. 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 - Intermittent failure, the vehicle is OK at this time. Check the SYSTEM CHECK and STATUS LOG information.
NO - Go to step 28.
6. Check to see if the immobilizer indicator comes on and blinks.
Does the indicator blink?
YES - Go to step 28.
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 - Go to step 43.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Remove the gauge assembly and disconnect its connectors.
11. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOLMP) terminal and body ground.
Is there continuity?
YES - Repair a short to ground in the wire.
NO - Faulty immobilizer indicator, replace the gauge assembly.
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. Measure the 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. 25 (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 (IMOLMP) terminal to ground.
Does the Indicator come on?
YES - Replace the immobilizer control unit-receiver.
NO - Go to step 17.
17. Remove the gauge assembly and disconnect connector A (22P).
18. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOLMP) terminal and gauge assembly connector A (22P) No. 4 terminal.
Is there continuity?
YES - Faulty immobilizer indicator, replace the immobilizer indicator bulb or gauge assembly.
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. Measure the voltage between the immobilizer control unit-receiver 7P connector No. 6 (IG1) terminal and body ground.
Is there battery voltage?
YES - Go to step 23.
NO - Faulty No. 2 (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. Measure the voltage between the immobilizer control unit-receiver 7P connector No. 1 (LG3) and No. 6 (IG1) 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. Jump the SCS line with the HDS.
26. Disconnect ECM connector E (31P).
27. Check for continuity between the immobilizer control unit-receiver 7P connector No. 1 (LG3) terminal and ECM connector E (31P) No. 3 (LG3) terminal.
Is there continuity?
YES - Check for a poor or loose connection at G101. If OK, substitute a known-good immobilizer control unit-receiver and recheck.
NO - Repair an open in the wire.
28. Turn the ignition switch OFF.
29. Connect the HDS to the data link connector.
30. Turn the ignition switch ON (II).
31. Go to the SYSTEM CHECK in IMMOBILIZER INFO of the HDS, and look for the following information on the display:
- Harness short from the ECM to the immobilizer control unit-receiver. (IMOCD (S-Net) line short)
- The communication was not good between the ECM and the immobilizer control unit-receiver by the battery voltage low.
- The communication was not good between the immobilizer control unit-receiver and the ECM by influence of some noise.
- Immobilizer control unit-receiver failure
- ECM failure
- Imoes unit failure
Does the HDS display any of the preceding information?
YES - Go to step 32.
NO - Go to step 37.
32. Turn the ignition switch OFF.
33. Disconnect the 7P connector from the immobilizer control unit-receiver.
34. Jump the SCS line with the HDS.
35. Disconnect ECM connector E (31P).
36. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 (IMOCD (S-Net)) terminal and body ground.
Is there continuity?
YES - Repair a short to ground in the wire.
NO - Go to step 43.
37. Verify the Status Log display on the HDS.
- Blown fuse
- Harness open from the ECM and the immobilizer control unit-receiver.
- The communication was not good between the ECM and the immobilizer control unit-receiver by battery voltage low.
- The communication was not good between the immobilizer control unit-receiver and the ECM by influence of some noise.
- Immobilizer control unit-receiver failure
- ECM failure
- Imoes unit failure
Does the HDS display any of the preceding information?
YES - Check the Possible Failures shown on the Status Log display.
NO - Go to step 38.
38. Turn the ignition switch OFF.
39. Disconnect the 7P connector from the immobilizer control unit-receiver.
40. Jump the SCS line with the HDS.
41. Disconnect ECM connector E (31P).
42. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 IMOCD (S-Net) terminal and ECM connector E (31P) No. 27 IMOCD (S-Net) terminal.
Is there continuity?
YES - Go to step 43.
NO - Repair an open in the wire.
43. Check for continuity between the imoes unit 5P connector No, 2 IMOCD (S-Net) terminal and ECM connector E (31P) No. 27 IMOCD (S-Net) terminal.
Is there continuity?
YES - Substitute a known-good imoes unit and/or immobilizer control unit-receiver, and recheck the system. If the imoes unit and/or immobilizer control unit-receiver is OK, substitute a known-good ECM, and recheck.
NO - Repair an open in the wire.