DTC U0056-00 (CAN Gateway) (2019 2020 2021)

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. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

2. Shorted unit check (gauge control module)

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

   -2. Disconnect the following connector.

   Gauge control module 32P 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 (Without navigation and ANC/active sound control system)

   Go to step 6.

   YES (Without navigation and with ANC/active sound control system)

   Go to step 5.

   YES (With navigation)

   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 gauge control module , then recheck. If DTC U0056-00 goes away and the gauge control module was substituted, replace the original gauge control module .

3. Shorted unit check (audio-navigation unit)

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

   -2. Disconnect the following connector.

   Audio-navigation unit connector C (24P)

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

4. 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.

   -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?

   1. YES 

      • Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good keyless access control unit , then recheck. If DTC U0056-00 goes away and the keyless access control unit was substituted, replace the original keyless access control unit .
      • If the original keyless access control unit is OK, go to step 5.

      NO 

      Substitute a known-good ANC/active sound control unit , then recheck. If DTC U0056-00 goes away and the ANC/active sound control unit was substituted, replace the original ANC/active sound control unit .

5. 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.

   -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 

   Substitute a known-good ANC/active sound control unit , then recheck. If DTC U0056-00 goes away and the ANC/active sound control unit was substituted, replace the original ANC/active sound control unit .

6. Shorted unit check (audio unit)

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

   -2. Disconnect the following connector.

   Audio unit connector C (24P)

   -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?

   1. YES 

      • Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good keyless access control unit , then recheck. If DTC U0056-00 goes away and the keyless access control unit was substituted, replace the original keyless access control unit .
      • If the original keyless access control unit is OK, go to step 7.

      NO 

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

7. 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
   	Gauge control module 32P connector: disconnected
   	Audio unit connector C (24P) (without navigation): disconnected
   	Audio-navigation unit connector C (24P) (with navigation): disconnected
   	ANC/active sound control unit 20P connector (with ANC/active sound control system): disconnected
   	Keyless access control unit connector C (20P) (with keyless access system): 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 

   Go to step 8.

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

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

   Test condition	Vehicle OFF (LOCK) mode
   	Gauge control module 32P connector: disconnected
   	Audio unit connector C (24P) (without navigation): disconnected
   	Audio-navigation unit connector C (24P) (with navigation): disconnected
   	ANC/active sound control unit 20P connector (with ANC/active sound control system): disconnected
   	Keyless access control unit connector C (20P) (with keyless access system): 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 

   Go to step 9.

9. 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
   	Gauge control module 32P connector: disconnected
   	Audio unit connector C (24P) (without navigation): disconnected
   	Audio-navigation unit connector C (24P) (with navigation): disconnected
   	ANC/active sound control unit 20P connector (with ANC/active sound control system): disconnected
   	Keyless access control unit connector C (20P) (with keyless access system): 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 away and the CAN gateway was substituted, replace the original CAN gateway .