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 ECM/PCM connector A (44P), then disconnect the HDS.
4. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 88-121 Ohms?
YES -
Go to step 36.
NO -
Go to step 5.
5. Disconnect the gauge control module (tach) 36P connector Gauge Control Module Replacement.
6. Disconnect the ABS modulator-control unit 25P connector (without VSA) Service and Repair or the VSA modulator-control unit 37P connector (with VSA) Service and Repair and the yaw rate-lateral acceleration sensor 4P connector (with VSA) Service and Repair.
7. Disconnect SRS unit connector A (28P) SRS Unit Replacement.
8. With EPS: Disconnect EPS control unit connector D (28P) Service and Repair.
9. With TPMS: Disconnect the TPMS control unit 20P connector Service and Repair.
10. Check for continuity between ECM/PCM connector terminals A36 and A37.
Is there continuity?
YES -
Repair short in the wires between ECM/PCM connector terminals A36 and A37.�
NO -
Go to step 11.
11. Check for continuity between ECM/PCM connector terminal A36 and gauge control module (tach) 36P connector terminal No. 1.
Is there continuity?
YES -
- With VSA: Go to step 12.
- Without VSA, but with EPS: Go to step 13.
- Without VSA and EPS: Go to step 14.
NO -
Repair open in the wire between the ECM/PCM (A36) and the gauge control module (tach).�
12. Check for continuity between ECM/PCM connector terminal A36 and VSA modulator-control unit 37P connector terminal No. 15.
Is there continuity?
YES -
- With EPS: Go to step 13.
- Without EPS: Go to step 14.
NO -
Repair open in the wire between the ECM/PCM (A36) and the VSA modulator-control unit.�
13. Check for continuity between ECM/PCM connector terminal A36 and EPS control unit connector D (28P) terminal No. 1.
Is there continuity?
YES -
Go to step 14.
NO -
Repair open in the wire between the ECM/PCM (A36) and the EPS control unit.�
14. Check for continuity between ECM/PCM connector terminal A37 and gauge control module (tach) 36P connector terminal No. 19.
Is there continuity?
YES -
- With VSA: Go to step 15.
- Without VSA, but with EPS: Go to step 16.
- Without VSA and EPS: Go to step 17.
NO -
Repair open in the wire between the ECM/PCM (A37) and the gauge control module (tach).�
15. Check for continuity between ECM/PCM connector terminal A37 and VSA modulator-control unit 37P connector terminal No. 1.
Is there continuity?
YES -
- With EPS: Go to step 16.
- Without EPS: Go to step 17.
NO -
Repair open in the wire between the ECM/PCM (A37) and the VSA modulator-control unit.�
16. Check for continuity between ECM/PCM connector terminal A37 and EPS control unit connector D (28P) terminal No. 15.
Is there continuity?
YES -
Go to step 17.
NO -
Repair open in the wire between the ECM/PCM (A37) and the EPS control unit.�
17. Reconnect the gauge control module (tach) 36P connector.
18. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 108-132 Ohms?
YES -
- Without VSA: Go to step 19.
- With VSA: Disconnect the gauge control module (tach) 36P connector, then go to step 22.
NO -
Substitute a known-good gauge control module (tach) Gauge Control Module Replacement, then reconnect ECM/PCM connector A (44P). If the HDS identifies the vehicle, replace the original gauge control module (tach) Gauge Control Module Replacement.�
19. Disconnect the gauge control module (tach) 36P connector.
20. Reconnect the ABS modulator-control unit 25P connector.
21. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 2.34-2.86 kOhms?
YES -
Disconnect the ABS modulator-control unit 25P connector, then go to step 28.
NO -
Substitute a known-good ABS modulator-control unit Service and Repair, then reconnect ECM/PCM connector A (44P). If the HDS identifies the vehicle, replace the original ABS modulator-control unit Service and Repair.�
22. Reconnect the VSA modulator-control unit 37P connector.
23. Measure the resistance between ECM/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, then reconnect ECM/PCM connector A (44P). If the HDS identifies the vehicle, replace the original VSA modulator-control unit Service and Repair.�
24. Disconnect the VSA modulator-control unit 37P connector.
25. Reconnect the yaw rate-lateral acceleration sensor 5P connector.
26. Measure the resistance between ECM/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, then reconnect ECM/PCM connector A (44P). If the HDS identifies the vehicle, replace the original yaw rate-lateral acceleration sensor Service and Repair.�
27. Disconnect the yaw rate-lateral acceleration sensor 5P connector.
28. Reconnect SRS unit connector A (28P).
29. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 2.34-2.86 kOhms?
YES -
- With EPS: Go to step 30.
- Without EPS, but with TPMS: Disconnect SRS unit connector A (28P), then go to step 34.
- Without EPS and TPMS: Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�
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 EPS control unit connector D (28P).
32. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 2.34-2.86 kOhms?
YES -
- With TPMS: Go to step 33.
- Without TPMS: Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�
NO -
Substitute a known-good EPS control unit Service and Repair. If the HDS identifies the vehicle, replace the original EPS control unit Service and Repair.�
33. Disconnect EPS control unit connector D (28P).
34. Reconnect the TPMS control unit 20P connector.
35. Measure the resistance between ECM/PCM connector terminals A36 and A37.
Is there about 2.34-2.86 kOhms?
YES -
Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�
NO -
Substitute a known-good TPMS control unit Service and Repair. If the HDS identifies the vehicle, replace the original TPMS control unit Service and Repair.�
36. Disconnect the gauge control module (tach) 36P connector Gauge Control Module Replacement.
37. Disconnect the ABS modulator-control unit 25P connector (without VSA) Service and Repair or the VSA modulator-control unit 37P connector (with VSA) Service and Repair and the yaw rate-lateral acceleration sensor 5P connector (with VSA) Service and Repair.
38. Disconnect SRS unit connector A (28P) SRS Unit Replacement.
39. With EPS: Disconnect EPS control unit connector D (28P) Service and Repair.
40. With TPMS: Disconnect the TPMS control unit 20P connector Service and Repair.
41. Check for continuity between ECM/PCM connector terminal A36 and body ground.
Is there continuity?
YES -
Repair short in the wire between ECM/PCM connector terminal A36 and the gauge control module (tach), the ABS modulator-control unit (without VSA), the VSA modulator-control unit (with VSA), the yaw rate-lateral acceleration sensor (with VSA), the SRS unit, the EPS control unit (with EPS), the TPMS control unit (with TPMS), or the DLC.�
NO -
Go to step 42.
42. Check for continuity between ECM/PCM connector terminal A37 and body ground.
Is there continuity?
YES -
Repair short in the wire between ECM/PCM connector terminal A37 and the gauge control module (tach), the ABS modulator-control unit (without VSA), the VSA modulator-control unit (with VSA), the yaw rate-lateral acceleration sensor (with VSA), the SRS unit, the EPS control unit (with EPS), the TPMS control unit (with TPMS), or the DLC.�
NO -
Go to step 43.
43. Reconnect all connectors.
44. Connect the HDS to the DLC.
45. Disconnect the gauge control module (tach) 36P connector.
46. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the gauge control module (tach) Gauge Control Module Replacement.�
NO -
- Without VSA: Go to step 47.
- With VSA: Turn the ignition switch to LOCK (0), then reconnect the gauge control module (tach) 36P connector, and go to step 51.
47. Turn the ignition switch to LOCK (0).
48. Reconnect the gauge control module (tach) 36P connector.
49. Disconnect the ABS modulator-control unit 25P connector.
50. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the ABS modulator-control unit Service and Repair.�
NO -
Turn the ignition switch to LOCK (0), then reconnect the ABS modulator-control unit 25P connector, and go to step 59.
51. Disconnect the VSA modulator-control unit 37P connector.
52. 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 53.
53. Turn the ignition switch to LOCK (0).
54. Reconnect the VSA modulator-control unit 37P connector.
55. Disconnect yaw rate-lateral acceleration sensor 5P connector.
56. 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 57.
57. Turn the ignition switch to LOCK (0).
58. Reconnect the yaw rate-lateral acceleration sensor 5P connector.
59. Disconnect SRS unit connector A (28P).
60. 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 -
- With EPS: Go to step 61.
- Without EPS, but with TPMS: Turn the ignition switch to LOCK (0), then reconnect SRS unit connector A (28P), and go to step 66.
- Without EPS and TPMS: Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�
61. Turn the ignition switch to LOCK (0).
62. Reconnect SRS unit connector A (28P).
63. Disconnect EPS control unit connector D (28P).
64. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Replace the EPS control unit Service and Repair.�
NO -
- With TPMS: Go to step 65.
- Without TPMS: Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�
65. Turn the ignition switch to LOCK (0).
66. Disconnect the TPMS control unit 20P connector.
67. 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 -
Reconnect all connectors, then update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the HDS identifies the vehicle and the ECM/PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair.�