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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 31.

NO - Go to step 5.






5. Disconnect these connectors:
- Gauge control module 32P. Gauge Control Module Replacement

- VSA modulator-control unit 36P. Service and Repair

- Yaw rate-lateral acceleration sensor 5P. Service and Repair

- SRS unit A (39P). SRS Unit Replacement

- TPMS control unit (20P). Service and Repair

- Navigation unit A (32P) (if equipped). Service and Repair

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

Is there continuity?
YES - Repair short in the wires between ECM/PCM connector terminals A3 and A4.

NO - Go to step 7.






7. Connect ECM/PCM connector terminal A3 to body ground with a jumper wire.






8. Check for continuity between gauge control module 32P connector terminal No. 30 and body ground.

Is there continuity?
YES - Go to step 9.

NO - Repair open in the wire between the ECM/PCM (A3) and the gauge control module.






9. Check for continuity between VSA modulator-control unit 36P connector terminal No. 14 and body ground.

Is there continuity?
YES - Go to step 10.

NO - Repair open in the wire between the ECM/PCM (A3) and the VSA modulator-control unit.






10. Connect ECM/PCM connector terminal A4 to body ground with a jumper wire.






11. Check for continuity between gauge control module 32P connector terminal No. 29 and body ground.

Is there continuity?
YES - Go to step 12.

NO - Repair open in the wire between the ECM/PCM (A4) and the gauge control module.






12. Check for continuity between VSA modulator-control unit 36P connector terminal No. 1 and body ground.

Is there continuity?
YES - Go to step 13.

NO - Repair open in the wire between the ECM/PCM (A4) and the VSA modulator-control unit.






13. Remove the jumper wire from the ECM/PCM connector.

14. Reconnect the gauge control module 32P connector.

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

Is there about 2.34-2.86 kOhms?
YES - Go to step 16.

NO - Substitute a known-good gauge control module, Gauge Control Module Replacement and reconnect ECM/PCM connector A. If the HDS identifies the vehicle, replace the original gauge control module. Gauge Control Module Replacement






16. Disconnect the gauge control module 32P connector.

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

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

Is there about 108-132 Ohms?
YES - Go to step 19.

NO - Substitute a known-good VSA modulator-control unit, Service and Repair and reconnect ECM/PCM connector A. If the HDS identifies the vehicle, replace the original VSA modulator-control unit. Service and Repair






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

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

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 yaw rate-lateral acceleration sensor, Service and Repair and reconnect ECM/PCM connector A. If the HDS identifies the vehicle, replace the original yaw rate-lateral acceleration sensor. Service and Repair






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

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

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

Is there about 2.34-2.86 kOhms?
YES - Go to step 25.

NO - Substitute a known-good SRS unit, SRS Unit Replacement and reconnect ECM/PCM connector A. If the HDS identifies the vehicle, replace the original SRS unit. SRS Unit Replacement






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

26. Reconnect the TPMS control unit 20P connector.

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

Is there about 2.34-2.86 kOhms?
YES -
- With navigation system: Go to step 28.

- Without navigation system: Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, Initial Inspection and Diagnostic Overview then recheck. If the HDS identifies the vehicle with a known-good ECM/PCM, 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. If the HDS identifies the vehicle, replace the original TPMS control unit. Service and Repair






28. Disconnect the TPMS control unit 20P connector.

29. Reconnect navigation unit connector A (32P).

30. 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 Initial Inspection and Diagnostic Overview, then recheck. If the HDS identifies the vehicle with a known-good ECM/PCM, replace the original ECM/PCM. Service and Repair

NO - Substitute a known-good navigation unit, Service and Repair and reconnect ECM/PCM connector A. If the HDS identifies the vehicle, replace the original navigation unit. Service and Repair






31. Disconnect these connectors:
- Gauge control module 32P. Gauge Control Module Replacement

- VSA modulator-control unit 36P. Service and Repair

- Yaw rate-lateral acceleration sensor 5P. Service and Repair

- SRS unit A (39P). SRS Unit Replacement

- TPMS control unit (20P). Service and Repair

- Navigation unit A (32P) (if equipped). Service and Repair

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

Is there continuity?
YES - Repair 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, or the DLC.

NO - Go to step 33.






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

Is there continuity?
YES - Repair 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, or the DLC.

NO - Go to step 34.






34. Reconnect all connectors.

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

36. Disconnect the gauge control module 32P connector.

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

Does the HDS identify the vehicle?
YES - Replace the gauge control module. Gauge Control Module Replacement

NO - Go to step 38.


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

39. Reconnect the gauge control module 32P connector.

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

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

Does the HDS identify the vehicle?
YES - Replace the VSA modulator-control unit. Service and Repair

NO - Go to step 42.


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

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

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

45. 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. Service and Repair

NO - Go to step 46.


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

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

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

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

Does the HDS identify the vehicle?
YES - Replace the SRS unit. SRS Unit Replacement

NO - Go to step 50.


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

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

52. Disconnect the TPMS control unit 20P connector.

53. 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 system: Go to step 54.

- Without navigation system: Update the ECM/PCM if it does not have the latest software, ECM/PCM Update or substitute a known-good ECM/PCM, Initial Inspection and Diagnostic Overview then recheck. If the HDS identifies the vehicle with a known-good ECM/PCM, replace the original ECM/PCM. Service and Repair



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

55. Reconnect the TPMS control unit 20P connector.

56. Disconnect navigation unit connector A (32P).

57. 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, Initial Inspection and Diagnostic Overview then recheck. If the HDS identifies the vehicle with a known-good ECM/PCM, replace the original ECM/PCM. Service and Repair


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