DTC U0599: DC-DC Converter Lost Communication With Battery Condition Monitor Module (35), U1220 (34) (Battery Condition Monitor Module) (2017)

DTC U0599  : Invalid Data Received From DC-DC Converter Control Module A DTC U1220  : DC-DC Converter Lost Communication With Battery Condition Monitor Module

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Electric Powertrain (2017) .

DTCs (HEV)

1. DTC check

   - 1. Turn the vehicle to the ON mode.

   - 2. Clear the DTCs with the HDS.

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

   - 4. Turn the vehicle to the ON mode, and wait 10 seconds.

   - 5. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U0599 Invalid Data Received From DC-DC Converter Control Module A

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U1220 DC-DC Converter Lost Communication With Battery Condition Monitor Module

   Is DTC U0599 or U1220 indicated?

   YES 

   Go to step 2.

   NO 

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

2. DTC check

   - 1. Check for CAN gateway system DTCs with the HDS.

   DTC Description	Confirmed DTC

   DTC (CAN GATEWAY)

   Are any DTCs indicated?

   YES 

   The failure is duplicated. Go to the troubleshooting for CAN gateway system DTC (s) - Refer to: Communication Systems DTC Troubleshooting Index (2017) .

   NO 

   Go to step 3.

3. Open wire check (IGB line)

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

   - 2. Remove the service plug and the IPU front cover.

   - 3. Remove the IPU upper cover.

   - 4. Disconnect the following connectors.

   DC-DC converter 4P connector

   - 5. Do the 12 volt battery terminal reconnection procedure.

   - 6. Turn the vehicle to the ON mode.

   - 7. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	DC-DC converter 4P connector: disconnected
   Test point 1	DC-DC converter 4P connector No. 4
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   Go to step 4.

   NO 

   Repair an open in the IGB wire between the DC-DC converter (No. 4) and the 12P junction connector.

4. Open wire check (F-CAN A lines)

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

   - 2. Do the 12 volt battery terminal disconnection procedure.

   - 3. Disconnect the following connector.

   Battery condition monitor module connector E (32P)

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

   F-CAM A_H line 

   Test condition	Vehicle OFF (LOCK) mode
   	Battery condition monitor module connector E (32P): disconnected
   	DC-DC converter 4P connector: disconnected
   Test point 1	Battery condition monitor module connector E (32P) No. 9 - Refer to: Battery Condition Monitor Module Connector for Inputs and Outputs (2017)
   Test point 2	DC-DC converter 4P connector No. 1

   F-CAN A_L line 

   Test point 1	Battery condition monitor module connector E (32P) No. 8 - Refer to: Battery Condition Monitor Module Connector for Inputs and Outputs (2017)
   Test point 2	DC-DC converter 4P connector No. 2

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

   Is there continuity?

   YES 

   Replace the DC-DC converter - Refer to: DC-DC Converter Removal and Installation (2017) .

   NO 

   Repair an open in the F-CAN wires between the DC-DC converter unit and the battery condition monitor module (E8, E9).