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F-CAN Circuit Troubleshooting




F-CAN Circuit Troubleshooting

1. Turn the ignition switch to LOCK (0).

2. Jump the SCS line with the HDS.

3. Disconnect ECM/PCM connector A (49P).

4. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 88-111 Ohms?

YES -

Go to step 28.

NO -

Go to step 5.

5. Disconnect these connectors:

- Gauge control module 32P Service and Repair.
- VSA modulator-control unit 36P.
- Yaw rate-lateral acceleration sensor 5P.
- SRS unit A (39P) Service and Repair.
- TPMS control unit (20P) Service and Repair.
- Navigation unit B (32P) (if equipped) Service and Repair.

6. Check for continuity between ECM/PCM connector terminals A3 and A4.





Is there continuity?

YES -

Repair a short in the wires between ECM/PCM connector terminals A3 and A4.

NO -

Go to step 7.

7. Check for continuity between ECM/PCM connector terminal A3 and gauge control module 32P connector terminal No. 30.





Is there continuity?

YES -

Go to step 8.

NO -

Repair an open in the wire between the ECM/PCM (A3) and the gauge control module.

8. Check for continuity between ECM/PCM connector terminal A3 and VSA modulator-control unit 36P connector terminal No. 14.





Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire between the ECM/PCM (A3) and the VSA modulator-control unit.

9. Check for continuity between ECM/PCM connector terminal A4 and gauge control module 32P connector terminal No. 29.





Is there continuity?

YES -

Go to step 10.

NO -

Repair an open in the wire between the ECM/PCM (A4) and the gauge control module.

10. Check for continuity between ECM/PCM connector terminal A4 and VSA modulator-control unit 36P connector terminal No. 1.





Is there continuity?

YES -

Go to step 11.

NO -

Repair an open in the wire between the ECM/PCM (A4) and the VSA modulator-control unit.

11. Reconnect the gauge control module 32P connector.

12. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 13.

NO -

Substitute a known-good gauge control module Service and Repair, and reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original gauge control module Service and Repair.

13. Disconnect the gauge control module 32P connector.

14. Reconnect the VSA modulator-control unit 36P connector.

15. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 108-132 Ohms?

YES -

Go to step 16.

NO -

Reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original VSA modulator-control unit.

16. Disconnect the VSA modulator-control unit 36P connector.

17. Reconnect the yaw rate-lateral acceleration sensor 5P connector.

18. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 19.

NO -

Substitute a known-good yaw rate-lateral acceleration sensor, and reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original yaw rate-lateral acceleration sensor.

19. Disconnect the yaw-rate lateral acceleration sensor 5P connector.

20. Reconnect SRS unit connector A (39P).

21. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 22.

NO -

Substitute a known-good SRS unit Service and Repair, and reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original SRS unit Service and Repair.

22. Disconnect SRS unit connector A (39P).

23. Reconnect the TPMS control unit 20P connector.

24. Measure the resistance between ECM/PCM connector terminals A3 and A4 .





Is there about 2.34-2.86 kOhms?

YES -

- With navigation: Go to step 25.
- Without navigation: Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.

NO -

Substitute a known-good TPMS control unit Service and Repair, and reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original TPMS control unit Service and Repair.

25. Disconnect the TPMS control unit 20P connector.

26. Reconnect navigation unit connector B (32P).

27. Measure the resistance between ECM/PCM connector terminals A3 and A4.





Is there about 2.34-2.86 kOhms?

YES -

Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.

NO -

Substitute a known-good navigation unit Service and Repair, and reconnect ECM/PCM connector A (49P). If the HDS identifies the vehicle, replace the original navigation unit Service and Repair.

28. Disconnect these connectors:

- Gauge control module 32P Service and Repair.
- VSA modulator-control unit 36P.
- Yaw rate-lateral acceleration sensor 5P.
- SRS unit A (39P) Service and Repair.
- TPMS control unit (20P) Service and Repair.
- Navigation unit B (32P) (if equipped) Service and Repair.

29. Check for continuity between ECM/PCM connector terminal A3 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the ECM/PCM (A3) and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the SRS unit, the TPMS control unit, the navigation unit (if equipped), or the DLC.

NO -

Go to step 30.

30. Check for continuity between ECM/PCM connector terminal A4 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the ECM/PCM (A4) and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the SRS unit, the TPMS control unit, the navigation unit (if equipped), or the DLC.

NO -

Go to step 31.

31. Reconnect all connectors.

32. Connect the HDS to the DLC Initial Inspection and Diagnostic Overview.

33. Disconnect the gauge control module 32P connector.

34. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the gauge control module Service and Repair.

NO -

Go to step 35.

35. Turn the ignition switch to LOCK (0).

36. Reconnect the gauge control module 32P connector.

37. Disconnect the VSA modulator-control unit 36P connector.

38. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the VSA modulator-control unit.

NO -

Go to step 39.

39. Turn the ignition switch to LOCK (0).

40. Reconnect the VSA modulator-control unit 36P connector.

41. Disconnect the yaw rate-lateral acceleration sensor 5P connector.

42. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the yaw rate-lateral acceleration sensor.

NO -

Go to step 43.

43. Turn the ignition switch to LOCK (0).

44. Reconnect the yaw rate-lateral acceleration sensor 5P connector.

45. Disconnect SRS unit connector A (39P).

46. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the SRS unit Service and Repair.

NO -

Go to step 47.

47. Turn the ignition switch to LOCK (0).

48. Reconnect SRS unit connector A (39P).

49. Disconnect the TPMS control unit 20P connector.

50. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the TPMS control unit Service and Repair.

NO -

- With navigation: Go to step 51.
- Without navigation: Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.

51. Turn the ignition switch to LOCK (0).

52. Reconnect the TPMS control unit 20P connector.

53. Disconnect navigation unit connector B (32P).

54. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the navigation unit Service and Repair.

NO -

Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.

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