F-CAN Circuit Troubleshooting

Engine

F-CAN Circuit Troubleshooting

1. F-CAN circuit resistance check:

-1. Turn the ignition switch to LOCK (0).

-2. Jump the SCS line with the HDS.

-3. Disconnect the following connector.

-4. Disconnect the HDS.

-5. Measure the resistance between test points 1 and 2.

Is there about 46-58 Ohms?
-YES- Go to step 12.
-NO- Go to step 2.

2. Shorted wire check (F CAN-H line to F CAN-L line):

-1. Disconnect the following connectors.
* Gauge control module 32P connector
* VSA modulator-control unit 38P connector
* Steering angle sensor 4P connector
* EPS control unit connector A (11P)
* Real time AWD control unit 24P connector (with real time AWD)
* SRS unit connector A (39P)
* TPMS control unit 20P connector
* Audio-navigation unit connector B (20P) (with navigation)

-2. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- Repair a short in the F CAN-H wire to F CAN-L wire between PCM terminals A3 and A4.
-NO- The F CAN-H wire and F CAN-L wires are not shorted. Go to step 3.

3. Open wire check (F CAN-H line) 1:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-H wire is not open. Go to step 4.
-NO- Repair an open in the F CAN-H wire between the PCM (A3) and the gauge control module.

4. Open wire check (F CAN-H line) 2:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-H wire is not open. Go to step 5.
-NO- Repair an open in the F CAN-H wire between the PCM (A3) and the VSA modulator-control unit.

5. Open wire check (F CAN-H line) 3:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES (with real time AWD)- The F CAN-H wire is not open. Go to step 6.
-YES (without real time AWD)- The F CAN-H wire is not open. Go to step 7.
-NO- Repair an open in the F CAN-H wire between the PCM (A3) and the EPS control unit.

6. Open wire check (F CAN-H line) 4:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-H wire is not open. Go to step 7.
-NO- Repair an open in the F CAN-H wire between the PCM (A3) and the real time AWD control unit.

7. Open wire check (F CAN-L line) 1:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-L wire is not open. Go to step 8.
-NO- Repair an open in the F CAN-L wire between the PCM (A4) and the gauge control module.

8. Open wire check (F CAN-L line) 2:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-L wire is not open. Go to step 9.
-NO- Repair an open in the F CAN-L wire between the PCM (A4) and the VSA modulator-control unit.

9. Open wire check (F CAN-L line) 3:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES (with real time AWD)- The F CAN-L wire is not open. Go to step 10.
-YES (without real time AWD)- The F CAN-L wire is not open. Go to step 11.
-NO- Repair an open in the F CAN-L wire between the PCM (A4) and the EPS control unit.

10. Open wire check (F CAN-L line) 4:

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- The F CAN-L wire is not open. Go to step 11.
-NO- Repair an open in the F CAN-L wire between the PCM (A4) and the real time AWD control unit.

11. VSA modulator-control unit internal resistance check:

-1. Reconnect VSA modulator-control unit 38P connector.

-2. Measure the resistance between test points 1 and 2.

Is there about 108-132 Ohms?
-YES- The VSA modulator-control unit is OK. Go to step 12.
-NO- Replace the original VSA modulator-control unit Service and Repair.

12. Shorted wire check (F CAN-H line):

-1. Disconnect the following connectors:
* Gauge control module 32P connector
* VSA modulator-control unit 38P connector
* Steering angle sensor 4P connector
* EPS control unit connector A (11P)
* Real time AWD control unit 24P connector (with real time AWD): disconnected
* SRS unit connector A (39P)
* TPMS control unit 20P connector
* Audio-navigation unit connector B (20P) (with navigation)

-2. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- Repair a short in the F CAN-H wire between PCM (A3) and the gauge control module, the VSA modulator-control unit, the steering angle sensor, the EPS control unit, the real time AWD control unit, the SRS unit, the TPMS control unit, the navigation unit, or the DLC.
-NO- The F CAN-H wire is OK. Go to step 13.

13. Shorted wire check (F CAN-L line):

-1. Check for continuity between test points 1 and 2.

Is there continuity?
-YES- Repair a short in the F CAN-L wire between PCM (A4) and the gauge control module, the VSA modulator-control unit, the steering angle sensor, the EPS control unit, the real time AWD control unit, the SRS unit, the TPMS control unit, the navigation unit, or the DLC.
-NO- The F CAN-L wire is OK. Go to step 14.

14. Gauge control module check:

-1. Reconnect all connectors.

-2. Connect the HDS to the DLC.

-3. Disconnect the following connector.

-4. 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 15.

15. VSA modulator-control unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the gauge control module 32P connector.

-3. Disconnect the following connector.

-4. Turn the ignition switch to ON (II).

Does the HDS identify the vehicle?
-YES- Replace the VSA modulator-control unit Service and Repair.
-NO- Go to step 16.

16. Steering angle sensor check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the VSA modulator-control unit 38P connector.

-3. Disconnect the following connector.

-4. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?
-YES- Replace the steering angle sensor Steering Angle Sensor Removal And Installation.
-NO- Go to step 17.

17. EPS control unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the steering angle sensor 4P connector.

-3. Disconnect the following connector.

-4. 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 real time AWD)- Go to step 18.
-NO (without real time AWD)- Go to step 19.

18. Real time AWD control unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect EPS control unit connector A (11P).

-3. Disconnect the following connector.

-4. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?
-YES- Replace the real time AWD control unit .
-NO- Go to step 19.

19. SRS unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect EPS control unit connector A (11P) or real time AWD control unit 24P connector.

-3. Disconnect the following connector.

-4. 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 (with navigation)- Go to step 20.
-NO (without navigation)- Go to step 21.

20. Audio-navigation unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect SRS unit connector A (39P).

-3. Disconnect the following connector.

-4. Turn the ignition switch to ON (II), and read the HDS.

Does the HDS identify the vehicle?
-YES- Replace the audio-navigation unit Audio-Navigation Unit Removal and Installation.
-NO- Go to step 21.

21. TPMS control unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the audio-navigation unit connector B (20P).

-3. Disconnect the following connector.

-4. 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- Update the PCM PCM Update if it does not have the latest software, or substitute a known-good PCM Service and Repair, then recheck. If the HDS identifies the vehicle and the PCM was updated, troubleshooting is complete. If the HDS identifies the vehicle and the PCM was substituted, replace the original PCM Service and Repair.