F-CAN Circuit Troubleshooting

F-CAN Circuit Troubleshooting

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

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.

Is there about 95-116 Ohms?
YES - Go to step 33.

NO - Go to step 5.






5. Disconnect the gauge control module 36P connector. Gauge Control Module Replacement

6. Disconnect the VSA modulator-control unit 46P connector, Service and Repair and the yaw rate-lateral acceleration sensor 4P connector. Service and Repair

7. Disconnect SRS unit connector A (28P). SRS Unit Replacement

8. Disconnect the TPMS unit 20P connector. Service and Repair

9. 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 10.






10. Connect PCM connector terminal A36 to body ground with a jumper wire.






11. Check for continuity between gauge control module 36P connector terminal No. 34 and body ground.

Is there continuity?
YES - Go to step 12.

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






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

Is there continuity?
YES - Go to step 13.

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






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

Is there continuity?
YES - Go to step 14.

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






14. Remove the jumper wire from PCM connector A (44P).

15. Connect PCM connector terminal A37 to body ground with a jumper wire.






16. Check for continuity between gauge control module 36P connector terminal No. 33 and body ground.

Is there continuity?
YES - Go to step 17.

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






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

Is there continuity?
YES - Go to step 18.

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






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

Is there continuity?
YES - Go to step 19.

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






19. Reconnect the gauge control module 36P connector.

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

Is there about 108-132 Ohms?
YES - Go to step 21.

NO - Substitute a known-good gauge control module. Gauge Control Module Replacement If the HDS identifies the vehicle, replace the original gauge control module. Gauge Control Module Replacement






21. Disconnect the gauge control module 36P connector.

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

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

Is there about 2.34-2.86 kOhms?
YES - Go to step 24.

NO - Substitute a known-good VSA modulator-control unit. Service and Repair If the HDS identifies the vehicle, replace the original VSA modulator-control unit. Service and Repair






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

25. Reconnect the yaw rate-lateral acceleration sensor 4P connector.

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

Is there about 2.34-2.86 kOhms?
YES - Go to step 27.

NO - Substitute a known-good yaw rate-lateral acceleration sensor. Service and Repair If the HDS identifies the vehicle, replace the original yaw rate-lateral acceleration sensor. Service and Repair






27. Disconnect the yaw rate-lateral acceleration connector.

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

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

Is there about 2.34-2.86 kOhms?
YES - Go to step 30.

NO - Substitute a known-good SRS unit. SRS Unit Replacement If the HDS identifies the vehicle, replace the original SRS unit. SRS Unit Replacement






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

31. Reconnect the TPMS unit 20P connector.

32. 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, Initial Inspection and Diagnostic Overview 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 TPMS unit. Service and Repair If the HDS identifies the vehicle, replace the original TPMS unit. Service and Repair






33. Disconnect the gauge control module 36P connector. Gauge Control Module Replacement

34. Disconnect the VSA modulator-control unit 46P connector Service and Repair and the yaw rate-lateral acceleration sensor 4P connector. Service and Repair

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

36. Disconnect the TPMS unit 20P connector. Service and Repair

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

Is there continuity?
YES - Repair short in the wire between the PCM connector terminal A36 and the gauge control module, the VSA modulator-control unit, the yaw late-lateral acceleration sensor, the SRS unit, the TPMS unit, or the DLC.

NO - Go to step 38.






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

Is there continuity?
YES - Repair short in the wire between PCM connector terminal A37 and the gauge control module, the VSA modulator-control unit, the yaw rate-lateral acceleration sensor, the SRS unit, the TPMS unit, or the DLC.

NO - Go to step 39.






39. Reconnect all connectors.

40. Connect the HDS to the DLC. Initial Inspection and Diagnostic Overview

41. Disconnect the gauge control module 36P connector.

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

Does the HDS identify the vehicle?
YES - Replace the gauge control module. Gauge Control Module Replacement

NO - Go to step 43.


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

44. Reconnect the gauge control module 36P connector.

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

46. 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 47.


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

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

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

50. 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 51.


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

52. Reconnect the yaw rate-lateral acceleration sensor 4P connector.

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

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

Does the HDS identify the vehicle?
YES - Replace the SRS unit. SRS Unit Replacement

NO - Go to step 55.


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

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

57. Disconnect the TPMS unit 20P connector.

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

Does the HDS identify the vehicle?
YES - Replace the TPMS unit. Service and Repair

NO - Update the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM, Initial Inspection and Diagnostic Overview then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM. Service and Repair