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 E (31P), then disconnect the HDS.
4. Measure the resistance between ECM/PCM connector terminals E11 and E24.
Is there about 99-121 Ohms?
YES - Go to step 24.
NO - Go to step 5.
5. Disconnect the gauge control module 36P connector. Service and Repair
6. Disconnect the VSA modulator-control unit 47P connector. Service and Repair
7. Disconnect the TPMS control unit 20P connector.
8. Check for continuity between ECM/PCM connector terminals E11 and E24.
Is there continuity?
YES - Repair short in the wires between ECM/PCM connector terminals E11 and E24.
NO - Go to step 9.
9. Connect ECM/PCM connector terminal E11 to body ground with a jumper wire.
10. Check for continuity between gauge control module 36P connector terminal No. 29 and body ground.
Is there continuity?
YES - Go to step 11.
NO - Repair open in the wire between the ECM/PCM (E11) and the gauge control module.
11. Check for continuity between VSA modulator-control unit 47P connector terminal No. 11 and body ground.
Is there continuity?
YES - Go to step 12.
NO - Repair open in the wire between the ECM/PCM (E11) and the VSA modulator-control unit.
12. Remove the jumper wire from ECM/PCM connector E (31P).
13. Connect ECM/PCM connector terminal E24 to body ground with a jumper wire.
14. Check for continuity between gauge control module 36P connector terminal No. 28 and body ground.
Is there continuity?
YES - Go to step 15.
NO - Repair open in the wire between the ECM/PCM (E24) and the gauge control module.
15. Check for continuity between VSA modulator-control unit 47P connector terminal No. 15 and body ground.
Is there continuity?
YES - Go to step 16.
NO - Repair open in the wire between the ECM/PCM (E24) and the VSA modulator-control unit.
16. Reconnect the gauge control module 36P connector.
17. Measure the resistance between ECM/PCM connector terminals E11 and E24.
Is there about 2.34-2.86 kOhms?
YES - Go to step 18.
NO - Substitute a known-good gauge control module. Service and Repair If the HDS identifies the vehicle, replace the original gauge control module. Service and Repair
18. Disconnect the gauge control module 36P connector.
19. Reconnect the VSA modulator-control unit 47P connector.
20. Measure the resistance between ECM/PCM connector terminals E11 and E24.
Is there about 112-136 kOhms?
YES - Go to step 21.
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
21. Disconnect the VSA modulator-control unit 47P connector.
22. Reconnect the TPMS control unit 20P connector.
23. Measure the resistance between ECM/PCM connector terminals E11 and E24.
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, Initial Inspection and Diagnostic Overview then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM. Service and Repair
NO - Substitute a known-good TPMS control unit. If the HDS identifies the vehicle, replace the original TPMS control unit.
24. Disconnect the gauge control module 36P connector. Service and Repair
25. Disconnect the VSA modulator-control unit 47P connector. Service and Repair
26. Disconnect the TPMS control unit 20P connector.
27. Check for continuity between ECM/PCM connector terminal E11 and body ground.
Is there continuity?
YES - Repair short in the wire between ECM/PCM connector terminal E11 and the gauge control module, the VSA modulator-control unit, the TPMS control unit, or the DLC.
NO - Go to step 28.
28. Check for continuity between ECM/PCM connector terminal E24 and body ground.
Is there continuity?
YES - Repair short in the wire between ECM/PCM connector terminal E24 and the gauge control module, the VSA modulator-control unit, the TPMS control unit, or the DLC.
NO - Go to step 29.
29. Reconnect all connectors.
30. Connect the HDS to the DLC. Initial Inspection and Diagnostic Overview
31. Disconnect the gauge control module 36P connector.
32. 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 33.
33. Turn the ignition switch to LOCK (0).
34. Reconnect the gauge control module 36P connector.
35. Disconnect the VSA modulator-control unit 47P connector.
36. 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 37.
37. Turn the ignition switch to LOCK (0).
38. Disconnect the VSA modulator-control unit 47P connector.
39. Disconnect the TPMS control unit 20P connector.
40. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES - Replace the TPMS control unit.
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, Initial Inspection and Diagnostic Overview then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM. Service and Repair