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Home >> Honda >> 2014 >> Accord Plug-In >> Repair and Diagnosis (Single Page) >> Brakes >> Brakes Control Systems >> Electric Servo Brake System - Diagnostics (Hybrid) >> DTC Troubleshooting >> DTC U0100-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Management ECU); DTC U0101-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With PCM (Gear System)); DTC U0104-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Driving Support System Control Unit); DTC U0122-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With VSA Modulator-control Unit); DTC U0155-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Gauge Control Module) (2017)
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DTC U0100-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Management ECU); DTC U0101-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With PCM (Gear System)); DTC U0104-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Driving Support System Control Unit); DTC U0122-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With VSA Modulator-control Unit); DTC U0155-00: F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Gauge Control Module) (2017)

NOTE: 

DTC Description DTC Freeze Frame
U0100-00 F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Management ECU)    
U0101-00 F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With PCM (Gear System)    
U0104-00 F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Driving Support System Control Unit)    
U0122-00 F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With VSA Modulator-control Unit)    
U0155-00 F-CAN Malfunction (Electric Servo Brake Control Unit Lost Communication With Gauge Control Module)    

DTC (Electric servo brake)

  1. CAN gateway system DTC check

    -1. Turn the vehicle to the ON mode.

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

    DTC Description DTC
    U0029-00 CAN Gateway F-CAN ch A Bus Off  
    U0047-00 CAN Gateway F-CAN ch B Bus Off  
    U0056-00 CAN Gateway F-CAN ch C Bus Off  
    U3000-49 CAN Gateway Internal Failure  

    Is DTC U0029-00, U0047-00, U0056-00, and/or U3000-49 indicated?

    YES 

    Go to the troubleshooting for CAN gateway system DTC (s).

    NO 

    Go to step 2.

  2. F-CAN circuit communication check (Receiving control unit)

    -1. Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

    F-CAN Bus Connected Unit Check

    Does the electric servo brake control unit detect the CAN gateway Bus channels B and C?

    Bus B is Not Available

    Go to step 3.

    Bus C is Not Available

    Go to step 4.

    Bus B and C is Available

    Go to step 5.

  3. Open wire check (F-CAN B_H, F-CAN B_L lines)

    -1. Turn the vehicle to the OFF (LOCK) mode with driver's door open.

    - 2. Wait for 3 minutes.

    NOTE:  Do not close the driver's door.

    - 3. Disconnect the following connectors.

    CAN gateway 24P connector
    Electric servo brake control unit 22P connector

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Electric servo brake control unit 22P connector: disconnected
    Test point 1 CAN gateway 24P connector No. 11
    Test point 2 Electric servo brake control unit 22P connector No. 15 - Refer to: Electric Servo Brake Control Unit Connector for Inputs and Outputs (2017)
    Test point 1 CAN gateway 24P connector No. 10
    Test point 2 Electric servo brake control unit 22P connector No. 14 - Refer to: Electric Servo Brake Control Unit Connector for Inputs and Outputs (2017)
    GHH257342Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_L and the F-CAN B_H wires are OK. Check for poor connections or loose terminals at the CAN gateway and the electric servo brake control unit. If they are OK, replace the pedal feel simulator - Refer to: Electric Servo Brake Control Unit/Pedal Feel Simulator Removal and Installation (2017) .

    NO 

    Repair an open in the F-CAN B_H and/or the F-CAN B_L wire (s) between the CAN gateway and the electric servo brake control unit.

  4. Open wire check (F-CAN C_H, F-CAN C_L lines)

    -1. Turn the vehicle to the OFF (LOCK) mode with driver's door open.

    - 2. Wait for 3 minutes.

    NOTE:  Do not close the driver's door.

    - 3. Disconnect the following connectors.

    CAN gateway 24P connector
    Electric servo brake control unit 22P connector

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Electric servo brake control unit 22P connector: disconnected
    Test point 1 CAN gateway 24P connector No. 9
    Test point 2 Electric servo brake control unit 22P connector No. 19 - Refer to: Electric Servo Brake Control Unit Connector for Inputs and Outputs (2017)
    Test point 1 CAN gateway 24P connector No. 8
    Test point 2 Electric servo brake control unit 22P connector No. 18 - Refer to: Electric Servo Brake Control Unit Connector for Inputs and Outputs (2017)
    GHH257343Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN C_L and the F-CAN C_H wires are OK. Check for poor connections or loose terminals at the CAN gateway and the electric servo brake control unit. If they are OK, replace the pedal feel simulator - Refer to: Electric Servo Brake Control Unit/Pedal Feel Simulator Removal and Installation (2017) .

    NO 

    Repair an open in the F-CAN C_H and/or the F-CAN C_L wire (s) between the CAN gateway and the electric servo brake control unit.

  5. F-CAN circuit communication check (Transmitting control unit)

    -1. Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

    F-CAN Bus Connected Unit Check

    According to the detected DTC on the following table, make sure that the transmitting control unit detects the CAN gateway Bus channel (s) normally.

    DTC Transmitting control unit Detected CAN getaway Bus channel (s) at normal
    U0100-00 PCM A, B
    U0101-00 PCM A, B
    U0104-00 Multipurpose camera unit C
    U0122-00 VSA modulator-control unit B, C
    U0155-00 Gauge control module A

    Is it detected normally?

    Detected normal

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control unit and the CAN gateway.

    U0100-00: PCM is Not Available for Bus A

    Go to step 6.

    U0100-00: PCM is Not Available for Bus B

    Go to step 7.

    U0101-00: PCM is Not Available for Bus A

    Go to step 6.

    U0101-00: PCM is Not Available for Bus B

    Go to step 7.

    U0104-00: Multipurpose camera unit is Not Available for Bus C

    Go to step 8.

    U0122-00: VSA modulator-control unit is Not Available for Bus B

    Go to step 7.

    U0122-00: VSA modulator-control unit is Not Available for Bus C

    Go to step 8.

    U0155-00: Gauge control module is Not Available for Bus A

    Go to step 6.

  6. Open wire check (F-CAN A_H, F-CAN A_L lines)

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

    - 2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

    DTC Connector
    - CAN gateway 24P connector
    U0100-00 PCM connector A (50P)
    U0101-00 PCM connector A (50P)
    U0155-00 Gauge control module connector A (32P)

    NOTE: 

    • Always short the SCS line with the HDS before removing PCM connector (s).
    • Jump the SCS line with the HDS, and wait more than 1 minute.

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Transmitting control unit connector (s) for indicated DTCs: disconnected
    DTC Circuit name Test point 1 (Receiving control unit) Test point 2 (Transmitting control unit)
    Connector Terminal Connector Terminal
    U0100-00 F-CAN A_H CAN gateway 24P connector No. 14 PCM connector A (50P) - Refer to: PCM Connector for Inputs and Outputs (2017) No. 37
    F-CAN A_L No. 15 No. 36
    U0101-00 F-CAN A_H CAN gateway 24P connector No. 14 PCM connector A (50P) - Refer to: PCM Connector for Inputs and Outputs (2017) No. 37
    F-CAN A_L No. 15 No. 36
    U0155-00 F-CAN A_H CAN gateway 24P connector No. 14 Gauge control module connector A (32P) - Refer to: Gauge Control Module Input Test (2015, 2017) No. 19
    F-CAN A_L No. 15 No. 20
    GHH257344Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN A_H and the F-CAN A_L wires are OK. According to the detected DTC on the following table, update, substitute, or replace the appropriate control unit.

    DTC Operation for transmitting control unit
    U0100-00 Check for poor connections or loose terminals at the CAN gateway and the PCM. If they are OK, substitute a known-good PCM - Refer to: PCM Removal and Installation (2017) , then recheck. If DTC U0100-00 goes away, replace the original PCM - Refer to: PCM Removal and Installation (2017) .
    U0101-00 Check for poor connections or loose terminals at the CAN gateway and the PCM. If they are OK, substitute a known-good PCM - Refer to: PCM Removal and Installation (2017) , then recheck. If DTC U0101-00 goes away, replace the original PCM - Refer to: PCM Removal and Installation (2017) .
    U0155-00 Check for poor connections or loose terminals at the CAN gateway and the gauge control module. If they are OK, substitute a known-good gauge control module , then recheck. If DTC U0155-00 goes away, replace the original gauge control module .

    NO 

    Repair an open in the F-CAN A_H and/or the F-CAN A_L wire (s) between the transmitting control unit and the CAN gateway.

  7. Open wire check (F-CAN B_H, F-CAN B_L lines)

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

    - 2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

    DTC Connector
    - CAN gateway 24P connector
    U0100-00 PCM connector A (50P)
    U0101-00 PCM connector A (50P)
    U0122-00 VSA modulator-control unit 21P connector

    NOTE: 

    • Always short the SCS line with the HDS before removing PCM connector (s).
    • Jump the SCS line with the HDS, and wait more than 1 minute.

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Transmitting control unit connector (s) for indicated DTCs: disconnected
    DTC Circuit name Test point 1 (Receiving control unit) Test point 2 (Transmitting control unit)
    Connector Terminal Connector Terminal
    U0100-00 F-CAN B_H CAN gateway 24P connector No. 11 PCM connector A (50P) - Refer to: PCM Connector for Inputs and Outputs (2017) No. 39
    F-CAN B_L No. 10 No. 38
    DTC Circuit name Test point 1 (Receiving control unit) Test point 2 (Transmitting control unit)
    Connector Terminal Connector Terminal
    U0101-00 F-CAN B_H CAN gateway 24P connector No. 11 PCM connector A (50P) - Refer to: PCM Connector for Inputs and Outputs (2017) No. 39
    F-CAN B_L No. 10 No. 38
    U0122-00 F-CAN B_H CAN gateway 24P connector No. 11 VSA modulator-control unit 21P connector - Refer to: VSA Modulator-Control Unit Connector for Inputs and Outputs (2015, 2017) No. 8
    F-CAN B_L No. 10 No. 15
    GHH257345Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_H and the F-CAN B_L wires are OK. According to the detected DTC on the following table, update, substitute, or replace the appropriate control unit.

    DTC Operation for transmitting control unit
    U0100-00 Check for poor connections or loose terminals at the CAN gateway and the PCM. If they are OK, substitute a known-good PCM - Refer to: PCM Removal and Installation (2017) , then recheck. If DTC U0100-00 goes away, replace the original PCM - Refer to: PCM Removal and Installation (2017) .
    U0101-00 Check for poor connections or loose terminals at the CAN gateway and the PCM. If they are OK, substitute a known-good PCM - Refer to: PCM Removal and Installation (2017) , then recheck. If DTC U0101-00 goes away, replace the original PCM - Refer to: PCM Removal and Installation (2017) .
    U0122-00 Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. If they are OK, replace the VSA modulator-control unit .

    NO 

    Repair an open in the F-CAN B_H and/or the F-CAN B_L wire (s) between the transmitting control unit and the CAN gateway.

  8. Open wire check (F-CAN C_H, F-CAN C_L lines)

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

    - 2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

    DTC Connector
    - CAN gateway 24P connector
    U0104-00 Multipurpose camera unit 20P connector
    U0122-00 VSA modulator-control unit 21P connector

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Transmitting control unit connector (s) for indicated DTCs: disconnected
    DTC Circuit name Test point 1 (Receiving control unit) Test point 2 (Transmitting control unit)
    Connector Terminal Connector Terminal
    U0104-00 F-CAN C_H CAN gateway 24P connector No. 9 Multipurpose camera unit 20P connector No. 2
    F-CAN C_L No. 8 No. 13
    U0122-00 F-CAN C_H CAN gateway 24P connector No. 9 VSA modulator-control unit 21P connector - Refer to: VSA Modulator-Control Unit Connector for Inputs and Outputs (2015, 2017) No. 9
    F-CAN C_L No. 8 No. 16
    GHH257346Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN C_H and the F-CAN C_L wires are OK. According to the detected DTC on the following table, update, substitute, or replace the appropriate control unit.

    DTC Operation for transmitting control unit
    U0104-00 Check for poor connections or loose terminals at the CAN gateway and the multipurpose camera unit. If they are OK, replace the multipurpose camera unit .
    U0122-00 Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. If they are OK, replace the VSA modulator-control unit .

    NO 

    Repair an open in the F-CAN C_H and/or the F-CAN C_L wire (s) between the transmitting control unit and the CAN gateway.