DTC : U0029-00 [6-Speed A/T (CAN Gateway)] (2019 2020)

DTC U0029-00  : CAN Gateway F-CAN ch A Bus Off

NOTE:  Before you troubleshoot, review the general troubleshooting information - Go to:

How to Troubleshoot the A/T System (6-Speed A/T)

How to Troubleshoot the Fuel and Emissions Systems

How to Troubleshoot the Brake Booster Pressure Monitoring System

DTC (CAN GATEWAY)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   - 2. Clear the DTC with the HDS.

   Clear DTC

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

   - 4. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 5. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot - Refer to:

   How to Troubleshoot the A/T System (6-Speed A/T)

   How to Troubleshoot the Brake Booster Pressure Monitoring System

   How to Troubleshoot the Fuel and Emissions Systems

2. Shorted unit check (PCM)

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

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

   SCS Short

   - 3. Disconnect the following connector.

   PCM connector A (51P)

   - 4. Turn the vehicle to the ON mode.

   - 5. Clear the DTC with the HDS.

   Clear DTC

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

   - 7. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 8. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 3.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM (6-Speed A/T) - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the PCM was substituted, replace the original PCM (6-Speed A/T) - Removal and Installation .

3. Shorted unit check (VSA modulator-control unit)

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

   - 2. Disconnect the following connector.

   VSA modulator-control unit 38P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 4.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or replace the VSA Modulator-Control Unit - Removal and Installation .

4. Shorted unit check (EPS control unit)

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

   - 2. Disconnect the following connector.

   EPS control unit connector B (8P)

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 5.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or replace the EPS Motor/Control Unit - Removal and Installation .

5. Shorted unit check (engine mount control unit)

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

   - 2. Disconnect the following connector.

   Engine mount control unit 16P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 6.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good Engine Mount Control Unit - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the engine mount control unit was substituted, replace the original Engine Mount Control Unit - Removal and Installation .

6. Shorted unit check (gauge control module)

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

   - 2. Disconnect the following connector.

   Gauge control module connector A (32P)

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES (2WD)

   Go to step 8.

   OK (AWD)

   Go to step 7.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good Gauge Control Module - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the gauge control module was substituted, replace the original Gauge Control Module - Removal and Installation .

7. Shorted unit check (i-VTM control unit)

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

   - 2. Disconnect the following connector.

   i-VTM control unit 24P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 8.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good i-VTM Control Unit (AWD) - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the i-VTM control unit was substituted, replace the original i-VTM Control Unit (AWD) - Removal and Installation .

8. Shorted unit check (ANC/active sound control unit)

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

   - 2. Disconnect the following connector.

   ANC/active sound control unit 20P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 9.

   NO 

   Substitute a known-good ANC/Active Sound Control Unit - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the ANC/active sound control unit was substituted, replace the original ANC/Active Sound Control Unit - Removal and Installation .

9. Shorted unit check (steering angle sensor)

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

   - 2. Disconnect the following connector.

   Steering angle sensor 4P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   Clear DTC

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

   - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

   - 7. Check for DTCs with the HDS.

   DTC Description	DTC
   U0029 CAN Gateway F-CAN ch A Bus Off

   Is DTC name = DTC indicated?

   YES 

   Go to step 10.

   NO 

   Substitute a known-good Steering Angle Sensor - Removal and Installation , then recheck.

   If DTC name = DTC goes away and the steering angle sensor was substituted, replace the original Steering Angle Sensor - Removal and Installation .

10. Shorted unit check (multipurpose camera unit)

    -1. Turn the vehicle to the OFF (LOCK) mode, and wait 3 seconds or more.

    - 2. Disconnect the following connector.

    Multipurpose camera unit 20P connector

    - 3. Turn the vehicle to the ON mode.

    - 4. Clear the DTC with the HDS.

    Clear DTC

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

    - 6. Turn the vehicle to the ON mode, and wait 6 seconds.

    - 7. Check for DTCs with the HDS.

    DTC Description	DTC
    U0029 CAN Gateway F-CAN ch A Bus Off

    Is DTC name = DTC indicated?

    YES 

    Go to step 11.

    NO 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good Multipurpose Camera Unit - Removal and Installation , then recheck.

    If DTC name = DTC goes away and the multipurpose camera unit was substituted, replace the original Multipurpose Camera Unit - Removal and Installation .

11. Shorted unit check (SRS unit)

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

    - 2. Disconnect the following connector.

    SRS unit connector A (39P)

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

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

    - 4. Turn the vehicle to the ON mode.

    - 5. Clear the DTC with the HDS.

    Clear DTC

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

    - 7. Turn the vehicle to the ON mode, and wait 6 seconds.

    - 8. Check for DTCs with the HDS.

    DTC Description	DTC
    U0029 CAN Gateway F-CAN ch A Bus Off

    Is DTC name = DTC indicated?

    YES 

    • 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 DTC name = DTC goes away and the keyless access/TPMS control unit was substituted, replace the original Keyless Access/TPMS Control Unit - Removal and Installation .

    • If the original keyless access/TPMS control unit is OK, go to step 12.

    NO 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good SRS unit - Go to: SRS Unit - Removal and Installation (2017 2018 2019 2020 2021) , then recheck.

    If DTC name = DTC goes away and the SRS unit was substituted, replace the original SRS unit - Go to: SRS Unit - Removal and Installation (2017 2018 2019 2020 2021) .

12. Shorted wire check (F-CAN A_H line)

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

    - 2. Disconnect the following connector.

    Keyless access/TPMS control unit connector C (20P)

    CAN gateway 16P connector

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (51P): disconnected
    	VSA modulator-control unit 38P connector: disconnected
    	EPS control unit connector B (6P): disconnected
    	Engine mount control unit 16P connector: disconnected
    	Gauge control module connector A (32P): disconnected
    	i-VTM control unit 24P connector: disconnected
    	ANC/active sound control unit 20P connector: disconnected
    	Steering angle sensor 4P connector: disconnected
    	Multipurpose camera unit 20P connector: disconnected
    	SRS unit connector A (39P): disconnected
    	Keyless access/TPMS control unit connector C (20P): disconnected
    	CAN gateway 16P connector: disconnected
    Test point 1	CAN gateway 16P connector (female terminals) No. 3: (1)
    Test point 2	Body ground

    Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the F-CAN A_H wire between the CAN gateway and the connected units.

    NO 

    Go to step 13.

13. Shorted wire check (F-CAN A_L line)

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (51P): disconnected
    	VSA modulator-control unit 38P connector: disconnected
    	EPS control unit connector B (6P): disconnected
    	Engine mount control unit 16P connector: disconnected
    	Gauge control module connector A (32P): disconnected
    	i-VTM control unit 24P connector: disconnected
    	ANC/active sound control unit 20P connector: disconnected
    	Steering angle sensor 4P connector: disconnected
    	Multipurpose camera unit 20P connector: disconnected
    	SRS unit connector A (39P): disconnected
    	Keyless access/TPMS control unit connector C (20P): disconnected
    	CAN gateway 16P connector: disconnected
    Test point 1	CAN gateway 16P connector (female terminals) No. 11: (1)
    Test point 2	Body ground

    Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the F-CAN A_L wire between the CAN gateway and the connected units.

    NO 

    Go to step 14.

14. Shorted wire check (F-CAN A_H line to F-CAN A_L line)

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (51P): disconnected
    	VSA modulator-control unit 38P connector: disconnected
    	EPS control unit connector B (6P): disconnected
    	Engine mount control unit 16P connector: disconnected
    	Gauge control module connector A (32P): disconnected
    	i-VTM control unit 24P connector: disconnected
    	ANC/active sound control unit 20P connector: disconnected
    	Steering angle sensor 4P connector: disconnected
    	Multipurpose camera unit 20P connector: disconnected
    	SRS unit connector A (39P): disconnected
    	Keyless access/TPMS control unit connector C (20P): disconnected
    	CAN gateway 16P connector: disconnected
    Test point 1	CAN gateway 16P connector (female terminals) No. 3: (1)
    Test point 2	CAN gateway 16P connector (female terminals) No. 11: (1)

    Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the F-CAN A_H wire to the F-CAN A_L wire between CAN gateway terminals No. 3 and No. 11.

    NO 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good CAN Gateway - Removal and Installation (2019 2020 2021) , then recheck.

    If DTC name = DTC goes away and the CAN gateway was substituted, replace the original CAN Gateway - Removal and Installation (2019 2020 2021) .