F-CAN Circuit Troubleshooting - Part 1

F-CAN Circuit Troubleshooting (Part 1)

NOTE: Information marked with an asterisk (*) applies to the CANL line.

1. Turn the ignition switch OFF.
2. Jump the SCS line with the HDS.
3. Disconnect PCM connector A (44P), then disconnect the HDS.
4. Measure resistance between PCM connector terminals A36 and A37.






Is there about 85 - 103 ohms ((with AcuraLink navigation system), 88 - 107 ohms. (with non-AcuraLink navigation system), or 91 - 111 ohms (without navigation system))?

YES - Go to "F-CAN Circuit Trouble shooting (Part 2)".

NO - Go to step 5.

5. Disconnect the gauge control module 36P connector.
6. Disconnect the VSA modulator-control unit 46P connector.
7. Disconnect SRS unit connector A (28P).
8. Disconnect the steering angle sensor 5P connector.
9. Disconnect the yaw rate-lateral acceleration sensor 4P connector.
10. Disconnect TPMS control unit 20P connector.
11. Disconnect the SH-AWD control unit connector A (20P).
12. With navigation system: Disconnect the navigation unit connector A (20P).
13. With AcuraLink system: Disconnect the AcuraLink control unit (XM receiver) connector A (20P).
14. Check for continuity between PCM connector terminals A36 and A37.






Is there continuity?

YES - Repair short in the wires between PCM connector terminals A36 and A37.

NO - Go to step 15.

15. Connect PCM connector terminal A36 to body around with a jumper wire.






16. Check for continuity between gauge control module 36P connector terminal No. 28 and body ground.






Is there continuity?

YES - Go to step 17.

NO - Repair open in the wire between the PCM (A36) and the gauge control module.

17. Check for continuity between VSA modulator-control unit 46P connector terminal No. 39 and body ground.






Is there continuity?

YES - Go to step 18.

NO - Repair open in the wire between the PCM (A36) and the VSA modulator-control unit.

18. Check for continuity between SRS unit connector A (28P) terminal No. 11 and body ground.






Is there continuity?

YES - Go to step 19.

NO - Repair open in the wire between the PCM (A36) and the SRS unit.

19. Check for continuity between steering angle sensor 5P connector terminal No. 4 and body ground.






Is there continuity?

YES - Go to step 20.

NO - Repair open in the wire between the PCM connector (A36) and the steering angle sensor.

20. Check for continuity between yaw rate-lateral acceleration sensor 4P connector terminal No. 3 and body ground.






Is there continuity?

YES - Go to step 21.

NO - Repair open in the wire between the PCM (A36) and the yaw rate-lateral acceleration sensor.

21. Check for continuity between TPMS control unit 20P connector terminal No. 1 and body ground.






Is there continuity?

YES - Go to step 22.

NO - Repair open in the wire between the PCM (A36) and the TPMS control unit.

22. Check for continuity between SH-AWD control unit connector A (20P) terminal No. 10 and body ground.






Is there continuity?

YES -
- With navigation system: Go to step 23.
- Without navigation system: Go to step 25.

NO - Repair open in the wire between the PCM (A36) and the SH-AWD control unit.

23. Check for continuity between navigation unit connector A (20P) terminal No. 8 and body ground.






Is there continuity?

YES -
- With AcuraLink system: Go to step 24.
- Without AcuraLink system: Go to step 25.

NO - Repair open in the wire between the PCM (A36) and the navigation unit.

24. Check for continuity between AcuraLink control unit (XM receiver) connector A (20P) terminal No. 6 and body ground.






Is there continuity?

YES - Go to step 25.

NO - Repair open in the wire between the PCM (A36) and the AcuraLink control unit (XM receiver).

25. Remove the jumper wire from PCM connector A (44P).
26. Connect PCM connector terminal A37 to body ground with a jumper wire.






27. Check for continuity between gauge control module 36P connector terminal No. 29 and body ground.






Is there continuity?

YES - Go to step 28.

NO - Repair open in the wire between the PCM (A37) and the gauge control module.

28. Check for continuity between VSA modulator-control unit 46P connector terminal No. 38 and body ground.






Is there continuity?

YES - Go to step 29.

NO - Repair open in the wire between the PCM (A37) and the VSA modulator-control unit.

29. Check for continuity between SRS unit connector A (28P) terminal No. 12 and body ground.






Is there continuity?

YES - Go to step 30.

NO - Repair open in the wire between the PCM (A37) and the SRS unit.

30. Check for continuity between steering angle sensor 5P connector terminal No. 2 and body ground.






Is there continuity?

YES - Go to step 31.

NO - Repair open in the wire between the PCM connector (A37) and the steering angle sensor.

31. Check for continuity between yaw rate-lateral acceleration sensor 4P connector terminal No. 2 and body ground.






Is there continuity?

YES - Go to step 32.

NO - Repair open in the wire between the PCM (A37) and the yaw rate-lateral acceleration sensor.

32. Check for continuity between TPMS control unit 20P connector terminal No. 11 and body ground.






Is there continuity?

YES - Go to step 33.

NO - Repair open in the wire between the PCM (A37) and the TPMS control unit.

33. Check for continuity between SH-AWD control unit connector A (20P) terminal No. 20 and body ground.






Is there continuity?

YES -
- With navigation system: Go to step 34.
- Without navigation system: Go to step 36.

NO - Repair open in the wire between the PCM (A37) and the SH-AWD control unit.

34. Check for continuity navigation unit connector A (20P) terminal No. 18 and body ground.






Is there continuity?

YES -
- With AcuraLink system: Go to step 35.
- Without AcuraLink system: Go to step 36.

NO - Repair open in the wire between the PCM (A37) and the navigation unit.

35. Check for continuity between AcuraLink control unit (XM receiver) connector A (20P) terminal No. 16 and body ground.






Is there continuity?

YES - Go to step 36.

NO - Repair open in the wire between the PCM (A37) and the AcuraLink control unit (XM receiver).

36. Reconnect the gauge control module 36P connector.
37. Measure resistance between PCM connector terminals A36 and A37.






Is there about 108 - 132 kohms?

YES - Go to step 38.

NO - Substitute a known-good gauge control module and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original gauge control module.

38. Disconnect the gauge control module 36P connector and PCM connector A (44P).
39. Reconnect the VSA modulator-control unit 46P connector.
40. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES - Go to step 41.

NO - Substitute a known-good VSA modulator-control unit and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original VSA modulator-control unit.

41. Disconnect the VSA modulator-control unit 46P connector and PCM connector A (44P).
42. Reconnect SRS unit connector A (28P).
43. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES - Go to step 44.

NO - Substitute a known-good SRS unit and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original SRS unit.

44. Disconnect SRS unit connector A (28P) and PCM connector A (44P).
45. Reconnect TPMS control unit 20P connector.
46. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES - Go to step 47.

NO - Substitute a known-good TPMS control unit and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original TPMS control unit.

47. Disconnect the TPMS control unit 20P connector and PCM connector A (44P).
48. Reconnect SH-AWD control unit connector A (20P).
49. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES -
- With navigation system: Go to step 50.
- Without navigation system: 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.

NO - Substitute a known-good SH-AWD control unit and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original SH-AWD control unit.

50. Disconnect SH-AWD control unit connector A (20P) and PCM connector A (44P).
51. Reconnect navigation unit connector A (20P).
52. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES -
- With AcuraLink system: Go to step 53.
- Without AcuraLink system: 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.

NO - Substitute a known-good navigation unit and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original navigation unit.

53. Disconnect navigation unit connector A (20P) and PCM connector A (44P).
54. Reconnect the AcuraLink control unit (XM receiver) connector A (20P).
55. Measure resistance between PCM connector terminals A36 and A37.






Is there about 2.34 - 2.86 kohms?

YES - 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.

NO - Substitute a known-good AcuraLink control unit (XM receiver) and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original AcuraLink control unit (XM receiver).