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F-CAN Circuit Troubleshooting - Part 1




F-CAN Circuit Troubleshooting - Part 1

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

2. Jump the SCS line with the HDS.

3. Disconnect PCM connector A (49P).

4. Measure the resistance between PCM connector terminals A48 and A49, then compare your reading to the model/trim level listed the table below.

Vehicles with active damper:





Vehicles without active damper:









Is the resistance OK?

YES -

Go to F-CAN circuit troubleshooting (Part 2).

NO -

Go to step 5.

5. Disconnect these connectors:

- Gauge control module connector A (12P) Service and Repair.
- VSA modulator-control unit 46P connector Service and Repair.
- Yaw rate-lateral/longitudinal acceleration sensor 4P connector Service and Repair.
- Steering angle sensor 5P connector Service and Repair.
- SRS unit connector A (39P) SRS Unit Replacement.
- TPMS control unit 20P connector Service and Repair.
- Active damper control unit connector B (14P) (with active damper) Service and Repair.
- SH-AWD control unit connector A (20P) Service and Repair.
- ACC unit 20P connector (with ACC) Service and Repair.
- E-pretensioner unit connector B (14P) (with ACC) Removal and Replacement.
- AcuraLink control unit connector A (32P) (USA model with AcuraLink) AcuraLink Control Unit (XM Receiver) Removal/Installation.

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





Is there continuity?

YES -

Repair a short in the wires between PCM connector terminals A48 and A49.�

NO -

Go to step 7.

7. Check for continuity between PCM connector terminal A48 and gauge control module connector A (12P) terminal No. 12.





Is there continuity?

YES -

Go to step 8.

NO -

Repair an open in the wire between the PCM(A48) and the gauge control module.�

8. Check for continuity between PCM connector terminal A48 and VSA modulator-control unit 46P connector terminal No. 39.





Is there continuity?

YES -

Go to step 9.

NO -

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

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





Is there continuity?

YES -

- With ACC: Go to step 10.
- Without ACC: Go to step 11.

NO -

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

10. Check for continuity between PCM connector terminal A48 and ACC unit 20P connector terminal No. 10.





Is there continuity?

YES -

Go to step 11.

NO -

Repair an open in the wire between the PCM (A48) and the ACC unit.�

11. Check for continuity between PCM connector terminal A49 and gauge control module connector A (12P) terminal No. 6.





Is there continuity?

YES -

Go to step 12.

NO -

Repair an open in the wire between the PCM(A49) and the gauge control module.�

12. Check for continuity between PCM connector terminal A49 and VSA modulator-control unit 46P connector terminal No. 38.





Is there continuity?

YES -

Go to step 13.

NO -

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

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





Is there continuity?

YES -

- With ACC: Go to step 14.
- Without ACC: Go to step 15.

NO -

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

14. Check for continuity between PCM connector terminal A49 and ACC unit 20P connector terminal No. 20.





Is there continuity?

YES -

Go to step 15.

NO -

Repair an open in the wire between the PCM (A49) and the ACC unit.�

15. Reconnect gauge control module connector A (12P).

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 17.

NO -

Substitute a known-good gauge control module Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original gauge control module Service and Repair.�

17. Disconnect gauge control module connector A (12P).

18. Reconnect the VSA modulator-control unit 46P connector.

19. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 108-132 Ohms?

YES -

Go to step 20.

NO -

Substitute a known-good VSA modulator-control unit Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original VSA modulator-control unit Service and Repair.�

20. Disconnect the VSA modulator-control unit 46P connector.

21. Reconnect the yaw rate-lateral/longitudinal acceleration sensor 4P connector.

22. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 23.

NO -

Substitute a known-good yaw rate-lateral/longitudinal acceleration sensor Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original yaw rate-lateral/longitudinal acceleration sensor Service and Repair.�

23. Disconnect the yaw rate-lateral/longitudinal acceleration sensor 4P connector.

24. Reconnect the steering angle sensor 5P connector.

25. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 26.

NO -

Substitute a known-good steering angle sensor Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original steering angle sensor Service and Repair.�

26. Disconnect the steering angle sensor 5P connector.

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

28. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 29.

NO -

Substitute a known-good SRS unit SRS Unit Replacement, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original SRS unit SRS Unit Replacement.�

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

30. Reconnect the TPMS control unit 20P connector.

31. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

- With active damper: Go to step 32.
- Without active damper: Go to step 35.

NO -

Substitute a known-good TPMS control unit Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original TPMS control unit Service and Repair.�

32. Disconnect the TPMS control unit 20P connector.

33. Reconnect active damper control unit connector B (14P).

34. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 35.

NO -

Substitute a known-good active damper control unit Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original active damper control unit Service and Repair.�

35. Disconnect the TPMS control unit 20P connector or active damper control unit connector B (14P).

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

37. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 108-132 Ohms?

YES -

- With ACC: Go to step 38.
- Without ACC: Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM Service and Repair.�

NO -

Substitute a known-good SH-AWD control unit Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original SH-AWD control unit Service and Repair.�

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

39. Reconnect the ACC unit 20P connector.

40. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 41.

NO -

Substitute a known-good ACC unit Service and Repair, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original ACC unit Service and Repair.�

41. Disconnect the ACC unit 20P connector.

42. Reconnect E-pretensioner unit connector B (14P).

43. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

- With AcuraLink: Go to step 44.
- Without AcuraLink: Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM Service and Repair.�

NO -

Substitute a known-good E-pretensioner unit Removal and Replacement, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original E-pretensioner unit Removal and Replacement.�

44. Disconnect E-pretensioner unit connector B (14P).

45. Reconnect AcuraLink control unit connector A (32P).

46. Measure the resistance between PCM connector terminals A48 and A49.





Is there about 2.34-2.86 kOhms?

YES -

Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM Service and Repair.�

NO -

Substitute a known-good AcuraLink control unit AcuraLink Control Unit (XM Receiver) Removal/Installation, then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original AcuraLink control unit AcuraLink Control Unit (XM Receiver) Removal/Installation.�

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