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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 PCM connector A (44P), then disconnect the HDS.

4. Measure the resistance between PCM connector terminals A36 and A37, then compare your reading to the model/trim level listed below.

Vehicle with SH-AWD:





Vehicle without SH-AWD:









Is the value of resistance OK?

YES -

Go to step 47.

NO -

Go to step 5.

5. Do the battery terminal disconnecting procedure Procedures, and wait at least 3 minutes before continuing.

6. Disconnect these connectors:

- Gauge control module 36P connector Service and Repair.
- VSA modulator-control unit 46P connector Service and Repair.
- SRS unit connector A (28P).
- Steering angle sensor 5P connector Service and Repair.
- Yaw rate-lateral acceleration sensor 4P connector Service and Repair.
- TPMS control unit 20P connector Service and Repair.
- SH-AWD control unit connector A (20P) (with SH-AWD) Service and Repair.
- Navigation unit connector A (20P) (if equipped) Service and Repair.
- AcuraLink control unit (XM receiver) connector A (20P) (if equipped) AcuraLink Control Unit-XM Receiver Removal/Installation.

7. Do the battery terminal reconnection procedure Procedures.

8. 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 9.

9. Check for continuity between PCM connector terminal A36 and gauge control module 36P connector terminal No. 28.





Is there continuity?

YES -

Go to step 10.

NO -

Repair an open in the wire between the PCM (A36) and the gauge control module.

10. Check for continuity between PCM connector terminal A36 and VSA modulator-control unit 46P connector terminal No. 39.





Is there continuity?

YES -

Go to step 11.

NO -

Repair an open in the wire between the PCM (A36) and the VSA modulator-control unit.

11. Check for continuity between PCM connector terminal A36 and SRS unit connector A (28P) terminal No. 11.





Is there continuity?

YES -

Go to step 12.

NO -

Repair an open in the wire between the PCM (A36) and the SRS unit.

12. Check for continuity between PCM connector terminal A36 and steering angle sensor 5P connector terminal No. 4.





Is there continuity?

YES -

Go to step 13.

NO -

Repair an open in the wire between the PCM (A36) and the steering angle sensor.

13. Check for continuity between PCM connector terminal A36 and yaw rate-lateral acceleration sensor 4P connector terminal No. 3.





Is there continuity?

YES -

Go to step 14.

NO -

Repair an open in the wire between the PCM (A36) and the yaw rate-lateral acceleration sensor.

14. Check for continuity between PCM connector terminal A36 and TPMS control unit 20P connector terminal No. 1.





Is there continuity?

YES -

- With SH-AWD: Go to step 15.
- Without SH-AWD with navigation: Go to step 16.
- Without SH-AWD and navigation: Go to step 18.

NO -

Repair an open in the wire between the PCM (A36) and the TPMS control unit.

15. Check for continuity between PCM connector terminal A36 and SH-AWD control unit connector A (20P) terminal No. 10.





Is there continuity?

YES -

- With navigation: Go to step 16.
- Without navigation: Go to step 18.

NO -

Repair an open in the wire between the PCM (A36) and the SH-AWD control unit.

16. Check for continuity between PCM connector terminal A36 and navigation unit connector A (20P) terminal No. 8.





Is there continuity?

YES -

- With AcuraLink: Go to step 17.
- Without AcuraLink: Go to step 18.

NO -

Repair an open in the wire between the PCM (A36) and the navigation unit.

17. Check for continuity between PCM connector terminal A36 and AcuraLink control unit (XM receiver) connector A (20P) terminal No. 6.





Is there continuity?

YES -

Go to step 18.

NO -

Repair an open in the wire between the PCM (A36) and the AcuraLink control unit (XM receiver).

18. Check for continuity between PCM connector terminal A37 and gauge control module 36P connector terminal No. 29.





Is there continuity?

YES -

Go to step 19.

NO -

Repair an open in the wire between the PCM (A37) and the gauge control module.

19. Check for continuity between PCM connector terminal A37 and VSA modulator-control unit 46P connector terminal No. 38.





Is there continuity?

YES -

Go to step 20

NO -

Repair an open in the wire between the PCM (A37) and the VSA modulator-control unit.

20. Check for continuity between PCM connector terminal A37 and SRS unit connector A (28P) terminal No. 12.





Is there continuity?

YES -

Go to step 21.

NO -

Repair an open in the wire between the PCM (A37) and the SRS unit.

21. Check for continuity between PCM connector terminal A37 and steering angle sensor 5P connector terminal No. 2.





Is there continuity?

YES -

Go to step 22.

NO -

Repair an open in the wire between the PCM connector (A37) and the steering angle sensor.

22. Check for continuity between PCM connector terminal A37 and yaw rate-lateral acceleration sensor 4P connector terminal No. 2.





Is there continuity?

YES -

Go to step 23.

NO -

Repair an open in the wire between the PCM (A37) and the yaw rate-lateral acceleration sensor.

23. Check for continuity between PCM connector terminal A37 and TPMS control unit 20P connector terminal No. 11.





Is there continuity?

YES -

- With SH-AWD: Go to step 24.
- Without SH-AWD with navigation: Go to step 25.
- Without SH-AWD and navigation: Go to step 27.

NO -

Repair an open in the wire between the PCM (A37) and the TPMS control unit.

24. Check for continuity between PCM connector terminal A37 and SH-AWD control unit connector A (20P) terminal No. 20.





Is there continuity?

YES -

- With navigation: Go to step 25.
- Without navigation: Go to step 27.

NO -

Repair an open in the wire between the PCM (A37) and the SH-AWD control unit.

25. Check for continuity PCM connector terminal A37 and navigation unit connector A (20P) terminal No. 18.





Is there continuity?

YES -

- With AcuraLink: Go to step 26.
- Without AcuraLink: Go to step 27.

NO -

Repair an open in the wire between the PCM (A37) and the navigation unit.

26. Check for continuity between PCM connector terminal A37 and AcuraLink control unit (XM receiver) connector A (20P) terminal No. 16.





Is there continuity?

YES -

Go to step 27.

NO -

Repair an open in the wire between the PCM (A37) and the AcuraLink control unit (XM receiver).

27. Reconnect the gauge control module 36P connector.

28. Measure the resistance between PCM connector terminals A36 and A37.





Is there about 108-132 Ohms (without SH-AWD) or 2.34-2.86 kOhms (with SH-AWD)?

YES -

Go to step 29.

NO -

Substitute a known-good gauge control module Service and Repair, then reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original gauge control module Service and Repair.

29. Disconnect the gauge control module 36P connector.

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

31. Measure the resistance between PCM connector terminals A36 and A37.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 32.

NO -

Replace the VSA modulator-control unit Service and Repair.

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

33. Reconnect SRS unit connector A (28P).

34. Measure the resistance between PCM connector terminals A36 and A37.





Is there about 2.34-2.86 kOhms?

YES -

Go to step 35.

NO -

Substitute a known-good SRS unit Service and Repair, then reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original SRS unit Service and Repair.

35. Disconnect SRS unit connector A (28P).

36. Reconnect TPMS control unit 20P connector.

37. Measure the resistance between PCM connector terminals A36 and A37.





Is there about 2.34-2.86 kOhms?

YES -

- With SH-AWD: Go to step 38.
- Without SH-AWD with navigation: Go to step 41.
- Without SH-AWD and navigation: 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 TPMS control unit Service and Repair, then reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original TPMS control unit Service and Repair.

38. Disconnect the TPMS control unit 20P connector.

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

40. Measure the resistance between PCM connector terminals A36 and A37.





Is there about 108-132 Ohms?

YES -

- With navigation: Go to step 41.
- Without navigation: Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away 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 (44P). If the HDS identifies the vehicle, replace the original SH-AWD control unit Service and Repair.

41. Disconnect SH-AWD control unit connector A (20P) (with SH-AWD) or the TPMS control unit 20P connector (without SH-AWD).

42. Reconnect navigation unit connector A (20P).

43. Measure the resistance between PCM connector terminals A36 and A37.





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 symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

NO -

Substitute a known-good navigation unit Service and Repair and reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original navigation unit Service and Repair.

44. Disconnect navigation unit connector A (20P).

45. Reconnect the AcuraLink control unit (XM receiver) connector A (20P).

46. Measure the 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 PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

NO -

Substitute a known-good AcuraLink control unit (XM receiver) AcuraLink Control Unit-XM Receiver Removal/Installation, then reconnect PCM connector A (44P). If the HDS identifies the vehicle, replace the original AcuraLink control unit (XM receiver) AcuraLink Control Unit-XM Receiver Removal/Installation.

47. Do the battery terminal disconnection procedure Procedures, and wait at least 3 minutes before starting work.

48. Disconnect these connectors:

- Gauge control module 36P connector Service and Repair.
- VSA modulator-control unit 46P connector Service and Repair.
- SRS unit connector A (28P).
- Steering angle sensor 5P connector Service and Repair.
- Yaw rate-lateral acceleration sensor 4P connector Service and Repair.
- TPMS control unit 20P connector Service and Repair.
- SH-AWD control unit connector A (20P) (with SH-AWD) Service and Repair.
- Navigation unit connector A (20P) (if equipped) Service and Repair.
- AcuraLink control unit (XM receiver) connector A (20P) (if equipped) AcuraLink Control Unit-XM Receiver Removal/Installation.

49. Do the battery terminal reconnection procedure Procedures.

50. Check for continuity between PCM connector terminal A36 and body ground.





Is there continuity?

YES -

Repair a short in the wire between PCM connector terminal A36 and the gauge control module, the VSA modulator-control unit, the SRS unit, the steering angle sensor, the yaw rate-lateral acceleration sensor, the TPMS control unit, the SH-AWD control unit, the navigation unit, the AcuraLink control unit (XM receiver), or the DLC.

NO -

Go to step 51.

51. Check for continuity between PCM connector terminal A37 and body ground.





Is there continuity?

YES -

Repair a short in the wire between PCM connector terminal A37 and the gauge control module, the VSA modulator-control unit, the SRS unit, the steering angle sensor, the yaw rate-lateral acceleration sensor, the TPMS control unit, the SH-AWD control unit, the navigation unit, the AcuraLink control unit (XM receiver), or the DLC.

NO -

Go to step 52.

52. Reconnect all connectors.

53. Connect the HDS to the DLC.

54. Disconnect the gauge control module 36P connector.

55. 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 56.

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

57. Reconnect the gauge control module 36P connector.

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

59. 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 60.

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

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

62. Disconnect SRS unit connector A (28P).

63. 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 64.

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

65. Reconnect SRS unit connector A (28P).

66. Disconnect the steering angle sensor 5P connector.

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

Does the HDS identify the vehicle?

YES -

Replace the steering angle sensor Service and Repair.

NO -

Go to step 68.

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

69. Reconnect the steering angle sensor 5P connector.

70. Disconnect the yaw rate-lateral acceleration sensor 4P connector.

71. 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 72.

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

73. Reconnect the yaw rate-lateral acceleration sensor.

74. Disconnect the TPMS control unit 20P connector.

75. 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 SH-AWD: Go to step 76.

- Without SH-AWD with navigation: Go to step 80.

- Without SH-AWD and navigation: Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

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

77. Reconnect the TPMS control unit 20P connector.

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

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

Does the HDS identify the vehicle?

YES -

Replace the SH-AWD control unit Service and Repair.

NO -

- With navigation: Go to step 80.
- Without navigation: Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

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

81. Reconnect SH-AWD control unit connector A (20P) (with SH-AWD) or the TPMS control unit 20P connector (without SH-AWD).

82. Disconnect navigation unit connector A (20P).

83. 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 -

- With AcuraLink: Go to step 84.
- 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 symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

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

85. Reconnect navigation unit connector A (20P).

86. Disconnect AcuraLink control unit (XM receiver) connector A (20P).

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

Does the HDS identify the vehicle?

YES -

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

NO -

Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.

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