F-CAN CIRCUIT TROUBLESHOOTING (2019 2020 2021: 9-Speed A/T)

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Jump the SCS line with the HDS, and wait more than 1 minute.

- 3. Disconnect the following connector.

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

F-CAN A circuit 

F-CAN B circuit 

- 5. Compare the results in step 1-4 with the following table.

Which pattern do the results match?

Pattern 1

Go to step 21.

Pattern 2

Go to step 2.

Pattern 3

Go to step 3.

Pattern 4

Go to step 2.

-1. Disconnect the following connectors.

NOTE:  Before disconnecting the SRS unit connector, do the 12 Volt Battery Terminal Disconnection procedure, and wait for at least 3 minutes.

• VSA modulator-control unit 38P connector
• TCM 58P connector
• SBW shifter control module 20P connector
• Engine mount control unit 16P connector
• Gauge control module connector A (32P)
• Steering angle sensor 4P connector
• ANC/active sound control unit 20P connector
• EPS control unit connector B (8P)
• Keyless access/TPMS control unit connector C (20P)
• SRS unit connector A (39P)

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

Is there continuity?

YES 

Repair a short in the F-CAN A_H wire to the F-CAN A_L wire between PCM terminals A10 and A11.

NO (Pattern 2)

The F-CAN A_H wire and the F-CAN A_L wire are not shorted. Go to step 4.

NO (Pattern 4)

The F-CAN A_H wire and the F-CAN A_L wire are not shorted. Go to step 3.

-1. If not already done, disconnect the following connectors.

• TCM 58P connector
• SBW shifter control module 20P connector

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

Is there continuity?

YES 

Repair a short in the F-CAN B_H wire to the F-CAN B_L wire between PCM terminals A12 and A13.

NO (Pattern 3)

The F-CAN B_H wire and the F-CAN B_L wire are not shorted. Go to step 16.

NO (Pattern 4)

The F-CAN B_H wire and the F-CAN B_L wire wires are not shorted. Go to step 4.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 5.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the gauge control module.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 6.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the VSA modulator-control unit.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 7.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the EPS control unit.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 8.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the engine mount control unit.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 9.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the keyless access/TPMS control unit.

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

Is there continuity?

YES 

The F-CAN A_H wire is not open. Go to step 10.

NO 

Repair an open in the F-CAN A_H wire between the PCM (A11) and the SRS unit.

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

Is there continuity?

YES 

The F-CAN A_L wire is not open. Go to step 11.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the gauge control module.

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

Is there continuity?

YES 

The F-CAN A_L wire is not open. Go to step 12.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the VSA modulator-control unit.

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

Is there continuity?

YES 

The F-CAN A_L wire is not open. Go to step 13.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the EPS control unit.

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

Is there continuity?

YES 

The F-CAN A_L wire is not open. Go to step 14.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the engine mount control unit.

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

Is there continuity?

YES 

The F-CAN A_L wire is not open. Go to step 15.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the keyless access/TPMS control unit.

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

Is there continuity?

YES (Pattern 2)

The F-CAN A_L wire is not open. Go to step 18.

YES (Pattern 4)

The F-CAN A_L wire is not open. Go to step 16.

NO 

Repair an open in the F-CAN A_L wire between the PCM (A10) and the SRS unit.

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

Is there continuity?

YES 

The F-CAN B_H wire is not open. Go to step 17.

NO 

Repair an open in the F-CAN B_H wire between the PCM (A13) and the TCM.

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

Is there continuity?

YES (Pattern 3)

The F-CAN B_L wire is not open. Go to step 20.

YES (Pattern 4)

The F-CAN B_L wire is not open. Go to step 18.

NO 

Repair an open in the F-CAN B_L wire between the PCM (A12) and the TCM.

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

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

Is there about 108 - 132 Ω?

YES 

The VSA modulator-control unit is OK. Disconnect the VSA modulator-control unit 38P connector, then go to step 19.

NO 

Replace the VSA Modulator-Control Unit - Removal and Installation .

-1. Reconnect EPS control unit connector B (8P).

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

Is there about 108 - 132 Ω?

YES (Pattern 4)

The EPS control unit is OK. Go to step 21.

YES (Pattern 4)

The EPS control unit is OK. Disconnect EPS control unit connector B (8P), then go to step 20.

NO 

Replace the EPS Motor/Control Unit - Removal and Installation .

-1. Reconnect the SBW shifter control module 20P connector.

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

Is there about 112 - 136 Ω?

YES (Pattern 3)

The SBW shifter control module is OK. Disconnect the SBW shifter control module 20P connector, then go to step 23.

YES (Pattern 4)

The SBW shifter control module is OK. Go to step 21.

NO 

Replace the SBW Shifter Assembly - Removal and Installation .

-1. Disconnect the following connectors.

NOTE:  Before disconnecting the SRS unit connector, do the 12 Volt Battery Terminal Disconnection procedure, and wait for at least 3 minutes.

• VSA modulator-control unit 38P connector
• TCM 58P connector
• SBW shifter control module 20P connector
• Engine mount control unit 16P connector
• Gauge control module connector A (32P)
• Steering angle sensor 4P connector
• ANC/active sound control unit 20P connector
• EPS control unit connector B (8P)
• Keyless access/TPMS control unit connector C (20P)
• SRS unit connector A (39P)

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

Is there continuity?

YES 

Repair a short in the F-CAN A_H wire between the PCM (A11) and the VSA modulator-control unit, the TCM, the SBW shifter control module, the engine mount control unit, the gauge control module, the steering angle sensor, the ANC/active sound control unit, the EPS control unit, the keyless access/TPMS control unit, the SRS unit, or the DLC.

NO 

The F-CAN A_H wire is OK. Go to step 22.

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

Is there continuity?

YES 

Repair a short in the F-CAN A_L wire between the PCM (A10) and the VSA modulator-control unit, the TCM, the SBW shifter control module, the engine mount control unit, the gauge control module, the steering angle sensor, the ANC/active sound control unit, the EPS control unit, the keyless access/TPMS control unit, the SRS unit, or the DLC.

NO 

The F-CAN A_L wire is OK. Go to step 23.

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

Is there continuity?

YES 

Repair a short in the F-CAN B_H wire between the PCM (A13) and the TCM, or the SBW shifter control module.

NO 

The F-CAN B_H wire is OK. Go to step 24.

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

Is there continuity?

YES 

Repair a short in the F-CAN B_L wire between the PCM (A12) and the TCM, or the SBW shifter control module.

NO 

The F-CAN B_L wire is OK. Go to step 25.

-1. Reconnect all connectors.

- 2. Connect the HDS to the DLC. How to Connect the HDS

- 3. Disconnect the following connector.

- 4. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the Gauge Control Module - Removal and Installation .

NO 

Reconnect the gauge control module connector A (32P) with vehicle in OFF (LOCK) mode, then go to step 26.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the VSA Modulator-Control Unit - Removal and Installation .

NO 

Reconnect the VSA modulator-control unit 38P connector with vehicle in OFF (LOCK) mode, then go to step 27.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the Steering Angle Sensor - Removal and Installation .

NO 

Reconnect the steering angle sensor 4P connector with vehicle in OFF (LOCK) mode, then go to step 28.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the EPS Motor/Control Unit - Removal and Installation .

NO 

Reconnect EPS control unit connector B (8P) with vehicle in OFF (LOCK) mode, then go to step 29.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the Engine Mount Control Unit - Removal and Installation .

NO 

Reconnect the engine mount control unit 16P connector with vehicle in OFF (LOCK) mode, then go to step 30.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the TCM - Removal and Installation .

NO 

Reconnect the TCM 58P connector with vehicle in OFF (LOCK) mode, then go to step 31.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the SBW Shifter Assembly Removal and Installation (9-Speed A/T) .

NO 

Reconnect the SBW shifter control module 20P connector with vehicle in OFF (LOCK) mode, then go to step 32.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connector.

- 3. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the ANC/Active Sound Control Unit Removal and Installation .

NO 

Reconnect the ANC/active sound control unit 20P connector with vehicle in OFF (LOCK) mode, then go to step 33.

-1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Do the 12 Volt Battery Terminal Disconnection procedure, and wait for at least 3 minutes.

- 3. Disconnect the following connector.

- 4. Do the 12 Volt Battery Terminal Reconnection procedure.

- 5. Turn the vehicle to the ON mode, and read the HDS.

Does the HDS identify the vehicle?

YES 

Replace the SRS unit - Go to: SRS Unit Removal and Installation (2017 2018 2019 2020 2021) .

NO 

• Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good Keyless Access/TPMS Control Unit - Removal and Installation , then recheck. If the HDS identifies the vehicle and the keyless access/TPMS control unit was substituted, replace the original Keyless Access/TPMS Control Unit - Removal and Installation .
• Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Go to: PCM Removal and Installation (9-Speed A/T) (2019 2020 2021), then recheck. If the HDS identifies the vehicle and the PCM was substituted, replace the original PCM - Go to: PCM Removal and Installation (9-Speed A/T) (2019 2020 2021) .