F-CAN Circuit Troubleshooting - Part 2

F-CAN Circuit Troubleshooting (Part 2)

1. Disconnect the gauge control module (tach) 36P connector.
2. Disconnect the ABS modulator-control unit 25P connector.
3. Disconnect the servo unit 25P connector.
4. Disconnect EPS control unit connector D (28P).
5. Disconnect SRS unit connector A (28P).
6. On vehicles with TPMS, disconnect the TPMS control unit 20P connector.
7. Remove the rear seat.
8. Turn the battery module switch OFF.
9. Remove the IPU lid.
10. Remove the BCM module.
11. Disconnect the MCM 20P connector.
12. Check for continuity between PCM connector terminal A36 and body ground.






Is there continuity?

YES - Repair short in the wire between PCM terminal A36 and the gauge control module (tach), the ABS modulator-control unit, the servo unit, the EPS control unit, the SRS unit, the BCM module, the MCM, the TPMS control unit (with TPMS), or the DLC

NO - Go to step 13.

13. Check for continuity between PCM connector terminal A37 and body ground.






Is there continuity?

YES - Repair short in the wire between PCM terminal A37 and the gauge control module (tach), the ABS modulator-control unit, the servo unit, the EPS control unit, the SRS unit, the BCM module, the MCM, the TPMS control unit (with TPMS), or the DLC.

NO - Go to step 14.

14. Reconnect all connectors.
15. Connect the HDS to the DLC.
16. Disconnect the gauge control module (tach) 36P connector.
17. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the gauge control module (tach).

NO - Go to step 18.

18. Turn the ignition switch OFF.
19. Reconnect the gauge control module (tach) 36P connector.
20. Disconnect the ABS modulator-control unit 25P connector.
21. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the ABS modulator-control unit.

NO - Go to step 22.

22. Turn the ignition switch OFF.
23. Reconnect the ABS modulator-control unit 25P connector.
24. Disconnect the servo unit 25P connector.
25. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the servo unit.

NO - Go to step 26.

26. Turn the ignition switch OFF.
27. Reconnect the servo unit 25P connector.
28. Disconnect EPS control unit connector D (28P).
29. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the EPS control unit.

NO - Go to step 30.

30. Turn the ignition switch OFF.
31. Reconnect EPS control unit connector D (28P).
32. Disconnect SRS unit connector A (28P).
33. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the SRS unit.

NO - Go to step 34.

34. Turn the ignition switch OFF.
35. Reconnect SRS unit connector A (28P).
36. Disconnect BCM module connector A (40P).
37. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the BCM module.

NO - Go to step 38.

38. Turn the ignition switch OFF.
39. Reconnect BCM module connector A (40P).
40. Disconnect the MCM 20P connector.
41. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the MCM.

NO -
- On vehicles with TPMS, go to step 42.
- On vehicles without TPMS, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.

42. Turn the ignition switch OFF.
43. Reconnect the MCM 20P connector.
44. Disconnect the TPMS control unit 20P connector.
45. Turn the ignition switch ON (II), and turn on the HDS.

Does the HDS identify the vehicle?

YES - Replace the TPMS control unit.

NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.