DTC U0056-00 (2018 2019 2020)

DTC U0056-00  : CAN Gateway F-CAN ch C Bus Off

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC (CAN gateway)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time.

2. 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.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 indicated?

   YES 

   Go to step 3.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or replace the VSA modulator-control unit .

3. 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.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 indicated?

   YES 

   Go to step 4.

   NO 

   Substitute a known-good steering angle sensor , then recheck. If DTC U0056-00 goes away and the steering angle sensor was substituted, replace the original steering angle sensor .

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 (6P)

   -3. Turn the vehicle to the ON mode.

   -4. Clear the DTC with the HDS.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 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 control unit .

5. Shorted unit check (precision all wheel steer control unit)

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

   -2. Disconnect the following connector.

   Precision all wheel steer control unit connector A (16P)

   -3. Turn the vehicle to the ON mode.

   -4. Clear the DTC with the HDS.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 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 precision all wheel steer control unit , then recheck. If DTC U0056-00 goes away and the precision all wheel steer control unit was substituted, replace the original precision all wheel steer control unit .

6. Shorted unit check (multipurpose camera unit)

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

   -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.

   -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
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 indicated?

   YES 

   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 multipurpose camera unit , then recheck. If DTC U0056-00 goes away and the multipurpose camera unit was substituted, replace the original multipurpose camera unit .

7. Shorted unit check (SRS unit)

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

   -2. Do the battery terminal disconnection procedure , then wait at least 3 minutes.

   -3. Disconnect the following connector.

   SRS unit connector A (39P)

   -4. Do the battery terminal reconnection procedure .

   -5. Turn the vehicle to the ON mode.

   -6. Clear the DTC with the HDS.

   -7. Turn the vehicle to the OFF (LOCK) mode.

   -8. Turn the vehicle to the ON mode, and wait 6 seconds.

   -9. Check for DTCs with the HDS.

   DTC Description	DTC
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 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 SRS unit , then recheck. If DTC U0056-00 goes way and the SRS unit was substituted, replace the original SRS unit .

8. Shorted unit check (E-pretensioner unit)

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

   -2. Do the battery terminal disconnection procedure , then wait at least 3 minutes.

   -3. Disconnect the following connectors.

   E-pretensioner unit connector A (16P)

   E-pretensioner unit connector B (14P)

   -4. Do the battery terminal reconnection procedure .

   -5. Turn the vehicle to the ON mode.

   -6. Clear the DTC with the HDS.

   -7. Turn the vehicle to the OFF (LOCK) mode.

   -8. Turn the vehicle to the ON mode, and wait 6 seconds.

   -9. Check for DTCs with the HDS.

   DTC Description	DTC
   U0056-00 CAN Gateway F-CAN ch C Bus Off

   Is DTC U0056-00 indicated?

   YES 

   Go to step 9.

   NO 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good E-pretensioner unit , then recheck. If DTC U0056-00 goes way and the E-pretensioner unit was substituted, replace the original E-pretensioner unit .

9. Shorted wire check (F-CAN C_H line)

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

   -2. Disconnect the following connector.

   CAN gateway 16P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	VSA modulator-control unit 38P connector: disconnected
   	Steering angle sensor 4P connector: disconnected
   	EPS control unit connector B (6P): disconnected
   	Precision all wheel steer control unit connector A (16P): disconnected
   	Multipurpose camera unit 20P connector: disconnected
   	SRS unit connector A (39P): disconnected
   	E-pretensioner unit connector A (16P): disconnected
   	E-pretensioner unit connector B (14P): disconnected
   	CAN gateway 16P connector: disconnected
   Test point 1	CAN gateway 16P connector (female terminals) No. 5:
   Test point 2	Body ground

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

   Is there continuity?

   YES 

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

   NO 

   The F-CAN C_H wire is not short to ground. Go to step 10.

10. Shorted wire check (F-CAN C_L line)

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

    Test condition	Vehicle OFF (LOCK) mode
    	VSA modulator-control unit 38P connector: disconnected
    	Steering angle sensor 4P connector: disconnected
    	EPS control unit connector B (6P): disconnected
    	Precision all wheel steer control unit connector A (16P): disconnected
    	Multipurpose camera unit 20P connector: disconnected
    	SRS unit connector A (39P): disconnected
    	E-pretensioner unit connector A (16P): disconnected
    	E-pretensioner unit connector B (14P): disconnected
    	CAN gateway 16P connector: disconnected
    Test point 1	CAN gateway 16P connector (female terminals) No. 13:
    Test point 2	Body ground

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

    Is there continuity?

    YES 

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

    NO 

    The F-CAN C_L wire is not short to ground. Go to step 11.

11. Shorted wire check (F-CAN C_H line to F-CAN C_L line)

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

    Test condition	Vehicle OFF (LOCK) mode
    	VSA modulator-control unit 38P connector: disconnected
    	Steering angle sensor 4P connector: disconnected
    	EPS control unit connector B (6P): disconnected
    	Precision all wheel steer control unit connector A (16P): disconnected
    	Multipurpose camera unit 20P connector: disconnected
    	SRS unit connector A (39P): disconnected
    	E-pretensioner unit connector A (16P): disconnected
    	E-pretensioner unit connector B (14P): disconnected
    	CAN gateway 16P connector: disconnected
    Test point 1	CAN gateway 16P connector (female terminals) No. 5:
    Test point 2	CAN gateway 16P connector (female terminals) No. 13:

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

    Is there continuity?

    YES 

    Repair a short in the F-CAN C_H wire to the F-CAN C_L wire between CAN gateway terminals No. 5 and No. 13.

    NO 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good CAN gateway , then recheck. If DTC U0056-00 goes way and the CAN gateway was substituted, replace the original CAN gateway .