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F-CAN Circuit Troubleshooting




F-CAN Circuit Troubleshooting

1. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

2. Jump the SCS line with the HDS.

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

4. Measure the resistance between ECM/PCM connector terminals A48 and A49.





Is there 74-107 Ohms?

YES -

Go to step 17.

NO -

Go to step 5.

5. Disconnect these connectors:

- Gauge control module 32P connector Service and Repair.
- VSA modulator-control unit 47P connector Service and Repair.
- EPS control unit connector D (28P) Service and Repair.
- SH-AWD control unit connector A (20P) (with SH-AWD) .
- Yaw rate-lateral acceleration sensor 4P connector Service and Repair.
- Steering angle sensor 5P connector (with SH-AWD) Service and Repair.
- SRS unit connector A (39P) Service and Repair.
- TPMS control unit 20P connector Service and Repair.
- Power control unit connector C (36P) (with keyless access).
- Audio-Navigation unit connector H (28P) (with navigation) Audio-Navigation Unit Removal/Installation.
- AcuraLink control unit connector A (32P) (USA model with navigation) AcuraLink Control Unit (XM Receiver) Removal/Installation.

6. Check for continuity between ECM/PCM connector terminals A48 and A49.





Is there continuity?

YES -

Repair short in the wires between ECM/PCM connector terminals A48 and A49.

NO -

Go to step 7.

7. Check for continuity between ECM/PCM connector terminals A48 and gauge control module 32P connector terminal No. 14.





Is there continuity?

YES -

Go to step 8.

NO -

Repair open in the wire between the ECM/PCM(A48) and the gauge control module.

8. Check for continuity between ECM/PCM connector terminals A48 and VSA modulator-control unit 47P connector terminal No. 12.





Is there continuity?

YES -

Go to step 9.

NO -

Repair open in the wire between the ECM/PCM(A48) and the VSA modulator-control unit.

9. Check for continuity between ECM/PCM connector terminals A48 and EPS control unit connector D (28P) terminal No. 1.





Is there continuity?

YES -

- With SH-AWD: Go to step 10.
- Without SH-AWD: Go to step 11.

NO -

Repair open in the wire between the ECM/PCM(A48) and the EPS control unit.

10. Check for continuity between ECM/PCM connector terminals A48 and SH-AWD control unit connector A (20P) terminal No. 10.





Is there continuity?

YES -

Go to step 11.

NO -

Repair open in the wire between the ECM/PCM(A48) and the SH-AWD control unit.

11. Check for continuity between ECM/PCM connector terminals A49 and gauge control module 32P connector terminal No. 13.





Is there continuity?

YES -

Go to step 12.

NO -

Repair open in the wire between the ECM/PCM(A49) and the gauge control module.

12. Check for continuity between ECM/PCM connector terminals A49 and VSA modulator-control unit 47P connector terminal No. 13.





Is there continuity?

YES -

Go to step 13.

NO -

Repair open in the wire between the ECM/PCM(A49) and the VSA modulator-control unit.

13. Check for continuity between ECM/PCM connector terminals A49 and EPS control unit connector D (28P) terminal No. 15.





Is there continuity?

YES -

- With SH-AWD: Go to step 14.
- Without SH-AWD: Go to step 15.

NO -

Repair open in the wire between the ECM/PCM(A49) and the EPS control unit.

14. Check for continuity between ECM/PCM connector terminals A49 and SH-AWD control unit connector A (20P) terminal No. 20.





Is there continuity?

YES -

Go to step 15.

NO -

Repair open in the wire between the ECM/PCM(A49) and the SH-AWD control unit.

15. Reconnect the VSA modulator-control unit 47P connector.

16. Measure the resistance between ECM/PCM connector terminals A48 and A49.





Is there about 108-132 Ohms?

YES -

Disconnect the VSA modulator-control unit 47P connector, then go to step 17.

NO -

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

17. Disconnect these connectors:

- Gauge control module 32P connector Service and Repair.
- VSA modulator-control unit 47P connector Service and Repair.
- EPS control unit connector D (28P) Service and Repair.
- SH-AWD control unit connector A (20P) (with SH-AWD) .
- Yaw rate-lateral acceleration sensor 4P connector Service and Repair.
- Steering angle sensor 5P connector (with SH-AWD) Service and Repair.
- SRS unit connector A (39P) Service and Repair.
- TPMS control unit 20P connector Service and Repair.
- Power control unit connector C (36P) (with keyless access).
- Audio-navigation unit connector H (28P) (with navigation) Audio-Navigation Unit Removal/Installation.
- AcuraLink control unit connector A (32P) (USA model with navigation) AcuraLink Control Unit (XM Receiver) Removal/Installation.

18. Check for continuity between ECM/PCM connector terminal A48 and body ground.





Is there continuity?

YES -

Repair short in the wire between the ECM/PCM terminals A48 and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the EPS control unit, the SH-AWD control unit (with SH-AWD), the steering angle sensor (with SH-AWD), the SRS unit, the TPMS control unit, the audio-navigation unit (with navigation), the AcuraLink control unit (USA model with navigation), the power control unit (with keyless access), or the DLC.

NO -

Go to step 19.

19. Check for continuity between ECM/PCM connector terminal A49 and body ground.





Is there continuity?

YES -

Repair short in the wire between the ECM/PCM terminals A49 and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the EPS control unit, the SH-AWD control unit (with SH-AWD), the steering angle sensor (with SH-AWD), the SRS unit, the TPMS control unit, the audio-navigation unit (with navigation), the AcuraLink control unit (USA model with navigation), the power control unit (with keyless access), or the DLC.

NO -

Go to step 20.

20. Reconnect all connectors.

21. Connect the HDS to the DLC.

22. Disconnect the gauge control module 32P connector.

23. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the gauge control module Service and Repair.

NO -

Go to step 24.

24. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

25. Reconnect the gauge control module 32P connector.

26. Disconnect the VSA modulator-control unit 47P connector.

27. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the VSA modulator-control unit Service and Repair.

NO -

Go to step 28.

28. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

29. Reconnect the VSA modulator-control unit 47P connector.

30. Disconnect EPS control unit connector D (28P).

31. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the EPS control unit Service and Repair.

NO -

- With SH-AWD: Go to step 32.
- Without SH-AWD: Turn the ignition switch to LOCK (0), or press the engine start/stop button to select OFF mode, then reconnect EPS control unit connector D (28P), and go to step 38.

32. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

33. Reconnect EPS control unit connector D (28P).

34. Disconnect SH-AWD control unit connector A (20P).

35. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the SH-AWD control unit .

NO -

Go to step 36.

36. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

37. Reconnect SH-AWD control unit connector A (20P).

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

39. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the yaw rate-lateral acceleration sensor Service and Repair.

NO -

- With SH-AWD: Go to step 40.
- Without SH-AWD: Turn the ignition switch to LOCK (0), or press the engine start/stop button to select OFF mode, then reconnect yaw rate-lateral acceleration sensor 5P connector, then go to step 46.

40. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

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

42. Disconnect the steering angle sensor 5P connector.

43. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the steering angle sensor Service and Repair.

NO -

Go to step 44.

44. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

45. Reconnect the steering angle sensor 5P connector.

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

47. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the SRS unit Service and Repair.

NO -

Go to step 48.

48. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

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

50. Disconnect the TPMS control unit 20P connector.

51. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the TPMS control unit Service and Repair.

NO -

- With keyless access: Go to step 52.
- Without keyless access: 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.

52. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

53. Reconnect the TPMS control unit 20P connector.

54. Disconnect power control unit connector C (36P).

55. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the power control unit.

NO -

- With navigation: Go to step 56.
- 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.

56. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

57. Reconnect power control unit connector C (36P).

58. Disconnect audio-navigation unit connector H (28P).

59. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the audio-navigation unit Audio-Navigation Unit Removal/Installation.

NO -

- USA model (with AcuraLink): Go to step 60.
- Canada model (without AcuraLink): 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.

60. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

61. Reconnect audio-navigation unit connector H (28P).

62. Disconnect AcuraLink control unit connector A (32P).

63. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES -

Replace the AcuraLink control unit AcuraLink Control Unit (XM Receiver) Removal/Installation.

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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