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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 (49P).

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





Is there about 85-105 Ohms?

YES -

Go to step 45.

NO -

Go to step 5.

5. Disconnect these connectors:

- Gauge control module connector B (28P) Service and Repair
- VSA modulator-control unit 36P connector Service and Repair
- Steering angle sensor 5P connector Service and Repair
- Yaw rate-acceleration sensor 5P connector Service and Repair
- SH-AWD control unit connector A (26P) Service and Repair
- TPMS control unit connector B (20P) Service and Repair
- Navigation unit connector B (32P) Service and Repair
- ACC (adaptive cruise control) unit 20P connector (if equipped) Service and Repair
- AcuraLink control unit (XM receiver) connector A (32P) (if equipped) AcuraLink Control Unit (XM Receiver) Removal/Installation
- E-pretensioner unit connector B (14P) (if equipped) Service and Repair

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 B (28P) terminal No. 16.





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 36P connector terminal No. 14.





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 terminals A48 and SH-AWD control unit connector A (26P) terminal No.11.





Is there continuity?

YES -

- With ACC (adaptive cruise control): Go to step 10.
- Without ACC, without AcuraLink: 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 B (28P) terminal No. 15.





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 36P connector terminal No. 1.





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 (26P) terminal No. 10.





Is there continuity?

YES -

- With ACC (adaptive cruise control): Go to step 14.
- Without ACC, without AcuraLink: 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 open in the wire between the PCM (A49) and the ACC unit.

15. Remove the jumper wire from the PCM connector.

16. Reconnect gauge control module connector B (28P).

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 18.

NO -

Substitute a known-good gauge control module Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original gauge control module Service and Repair.

18. Disconnect gauge control module connector B (28P).

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

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





Is there about 108-132 Ohms?

YES -

Go to step 21.

NO -

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

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

22. Reconnect SH-AWD control unit connector A (26P).

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 24.

NO -

Substitute a known-good SH-AWD control unit Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original SH-AWD control unit Service and Repair.

24. Disconnect SH-AWD control unit connector A (26P).

25. Reconnect the steering angle sensor 5P connector.

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 27.

NO -

Substitute a known-good steering angle sensor Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original steering angle sensor Service and Repair.

27. Disconnect the steering angle sensor 5P connector.

28. Reconnect the yaw rate-acceleration sensor 5P connector.

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 30.

NO -

Substitute a known-good yaw rate-acceleration sensor Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original yaw rate-acceleration sensor Service and Repair.

30. Disconnect the yaw rate-acceleration sensor 5P connector.

31. Reconnect TPMS control unit connector B (20P).

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 33.

NO -

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

33. Disconnect TPMS control unit connector B (20P).

34. Reconnect navigation unit connector B (32P).

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





Is there about 2.34-2.86 kOhms?

YES -

- With ACC (adaptive cruise control): Go to step 36.
- With AcuraLink, without ACC: Go to step 42.
- Without ACC, 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 navigation unit Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original navigation unit Service and Repair.

36. Disconnect navigation unit connector B (32P).

37. Reconnect the ACC unit 20P connector.

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





Is there about 2.34-2.86 kOhms?

YES -

Go to step 39.

NO -

Substitute a known-good ACC unit Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original ACC unit Service and Repair.

39. Disconnect the ACC unit 20P connector.

40. Reconnect e-pretensioner unit connector B (14P).

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





Is there about 2.34-2.86 kOhms?

YES -

- With AcuraLink: Go to step 42.
- 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 Service and Repair, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original e-pretensioner unit Service and Repair.

42. Disconnect e-pretensioner unit connector B (14P).

43. Reconnect AcuraLink control unit (XM receiver) connector A (32P).

44. 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 (XM receiver) AcuraLink Control Unit (XM Receiver) Removal/Installation, then reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original AcuraLink control unit (XM receiver) AcuraLink Control Unit (XM Receiver) Removal/Installation.

45. Disconnect these connectors:

- Gauge control module connector B (28P) Service and Repair
- VSA modulator-control unit 36P connector Service and Repair
- Steering angle sensor 5P connector Service and Repair
- Yaw rate-acceleration sensor 5P connector Service and Repair
- SH-AWD control unit connector A (26P) Service and Repair
- TPMS control unit connector B (20P) Service and Repair
- Navigation unit connector B (32P) Service and Repair
- ACC (adaptive cruise control) unit 20P connector (if equipped) Service and Repair
- AcuraLink control unit (XM receiver) connector A (32P) (if equipped) AcuraLink Control Unit (XM Receiver) Removal/Installation
- E-pretensioner unit connector B (14P) (if equipped) Service and Repair

46. Check for continuity between PCM connector terminal E15 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the PCM (A48) and the gauge control module, the VSA modulator-control unit, the steering angle sensor, the yaw rate-acceleration sensor, the SH-AWD control unit, the TPMS control unit, the navigation unit, the ACC unit, the e-pretensioner unit, the AcuraLink control unit (XM receiver), or the DLC.

NO -

Go to step 47.

47. Check for continuity between PCM connector terminal A49 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the PCM (A49) and the gauge control module, the VSA modulator-control unit, the steering angle sensor, the yaw rate-acceleration sensor, the SH-AWD control unit, the TPMS control unit, the navigation unit, the ACC unit, the e-pretensioner unit, the AcuraLink control unit (XM receiver), or the DLC.

NO -

Go to step 48.

48. Reconnect all connectors.

49. Connect the HDS to the DLC.

50. Disconnect gauge control module connector B (28P).

51. 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 52.

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

53. Reconnect gauge control module connector B (28P).

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

55. 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 56.

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

57. Reconnect VSA modulator-control unit 36P connector.

58. Disconnect the steering angle sensor 5P connector.

59. 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 60.

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

61. Reconnect the steering angle sensor 5P connector.

62. Disconnect yaw rate-acceleration sensor 5P connector.

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

Does the HDS identify the vehicle?

YES -

Replace the yaw rate-acceleration sensor Service and Repair.

NO -

Go to step 64.

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

65. Reconnect the yaw rate-acceleration sensor 5P connector.

66. Disconnect SH-AWD control unit connector A (26P).

67. 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 -

Go to step 68.

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

69. Reconnect the SH-AWD control unit connector A (26P).

70. Disconnect TPMS control unit connector B (20P).

71. 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 -

Go to step 72.

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

73. Reconnect TPMS control unit connector B (20P).

74. Disconnect navigation unit connector B (32P).

75. 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 ACC (adaptive cruise control): Go to step 76.
- With AcuraLink, without ACC: Go to step 80.
- Without ACC, 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.

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

77. Reconnect navigation unit connector B (32P).

78. Disconnect the ACC unit 20P connector.

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

Does the HDS identify the vehicle?

YES -

Replace the ACC unit Service and Repair.

NO -

Go to step 80.

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

81. Reconnect the ACC unit 20P connector.

82. Disconnect e-pretensioner unit connector B (14P).

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

Does the HDS identify the vehicle?

YES -

Replace the e-pretensioner 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 HDS identifies the vehicle with a known-good PCM, replace the original PCM Service and Repair.

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

85. Reconnect e-pretensioner unit connector B (14P).

86. Disconnect AcuraLink control unit (XM receiver) connector A (32P).

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 HDS identifies the vehicle with a known-good PCM, replace the original PCM Service and Repair.

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