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Component Tests and General Diagnostics




Engine

F-CAN Circuit Troubleshooting

F-CAN Circuit Troubleshooting

1. F-CAN circuit resistance check:

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. Measure the resistance between test points 1 and 2.









Is there about 46-58Ohms?
-YES- Go to step 15.
-NO- Go to step 2.

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

Shorted wire check (F_CAN-H line to F_CAN-L line)
-1. Disconnect the following connectors.
* Gauge control module (tach) 36P connector
* VSA modulator-control unit 22P connector
* Steering angle sensor 4P connector
* EPS control unit connector A (11P)
* Servo unit 25P connector
* MCM connector A (32P)
* SRS unit connector A (39P)
* Audio-navigation unit connector B (20P) (with navigation)
* TPMS control unit 20P connector

-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 wire is OK. Go to step 3.

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

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 (tach).

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

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:

Open wire check (F_CAN-H line) 3
-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 6.
-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:

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 servo unit.

7. Open wire check (F_CAN-H, CANH lines) 5:

Open wire check (F_CAN-H, CANH lines) 5
-1. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The F_CAN-H/CANH wires are OK. Go to step 8.
-NO- Repair an open in the F_CAN-H/CANH wire between the PCM (A3) and the MCM.

8. Open wire check (F_CAN-L line) 1:

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 9.
-NO- Repair an open in the F_CAN-L wire between the PCM (A4) and the gauge control module (tach).

9. Open wire check (F_CAN-L line) 2:

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 10.
-NO- Repair an open in the F_CAN-L wire between the PCM (A4) and the VSA modulator-control unit.

10. Open wire check (F_CAN-L line) 3:

Open wire check (F_CAN-L line) 3
-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 EPS control unit.

11. Open wire check (F_CAN-L line) 4:

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 12.
-NO- Repair an open in the F_CAN-L wire between the PCM (A4) and the servo unit.

12. Open wire check (F_CAN-L, CANL lines) 5:

Open wire check (F_CAN-L, CANL lines) 5
-1. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The F_CAN-L/CANL wires are OK. Go to step 13.
-NO- Repair an open in the F_CAN-L/CANL wire between the PCM (A4) and the MCM.

13. VSA unit internal resistance check:

VSA unit internal resistance check
-1. Reconnect VSA modulator-control unit 22P 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 14.
-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.

14. MCM internal resistance check:

MCM internal resistance check
-1. Disconnect the following connector.





-2. Reconnect MCM connector A (32P).

-3. Measure the resistance between test points 1 and 2.









Is there about 108-132 Ohms?
-YES- The MCM is OK. Go to step 15.
-NO- Substitute a known-good MCM Motor Control Module (MCM) Removal And Installation, and reconnect PCM connector A (49P). If the HDS identifies the vehicle, replace the original MCM Motor Control Module (MCM) Removal And Installation.

15. Shorted wire check (F_CAN-H line):

Shorted wire check (F_CAN-H line)
-1. Disconnect the following connectors:
* Gauge control module (tach) 36P connector
* VSA modulator-control unit 22P connector
* Steering angle sensor 4P connector
* EPS control unit connector A (11P)
* Servo unit 25P connector
* MCM connector A (32P)
* SRS unit connector A (39P)
* Audio-navigation unit connector B (20P) (with navigation)
* TPMS control unit 20P connector

-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 terminal A3 and the gauge control module (tach), the VSA modulator-control unit, the steering angle sensor, the EPS control unit, the servo unit, the SRS unit, the MCM, the audio-navigation unit, or the DLC.
-NO- The F_CAN-H wire is OK. Go to step 16.

16. Shorted wire check (F_CAN-L line):

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 terminal A4 and the gauge control module (tach), the VSA modulator-control unit, the steering angle sensor, the EPS control unit, the servo unit, the SRS unit, the MCM, the audio-navigation unit, or the DLC.
-NO- The F_CAN-L wire is OK. Go to step 17.

17. Gauge control module (tach) check:

Gauge control module (tach) 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 (tach) Gauge Control Module (Tach) Removal And Installation.
-NO- Go to step 18.

18. VSA modulator-control unit check:

VSA modulator-control unit check
-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the gauge control module (tach) 32P 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 VSA modulator-control unit Service and Repair.
-NO- Go to step 19.

19. Steering angle sensor check:

Steering angle sensor check
-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the VSA modulator-control unit 22P 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 20.

20. EPS control unit check:

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- Go to step 21.

21. Servo unit check:

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

-2. Reconnect the 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 servo unit Service and Repair.
-NO- Go to step 22.

22. SRS unit check:

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

-2. Reconnect the servo unit 25P 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- Go to step 23.

23. TPMS control unit check:

TPMS control unit check
-1. Turn the ignition switch to LOCK (0).

-2. Reconnect the 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 TPMS control unit Service and Repair.
-NO- Go to step 24.

24. MCM check:

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

-2. Reconnect the 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 MCM Motor Control Module (MCM) Removal And Installation.
-NO- With navigation: Go to step 25.
-NO- Without navigation: 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.

25. Navigation unit check:

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

-2. Reconnect the MCM connector A (32P).

-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.
-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.
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