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DTC U0100, U0122 (Body Control Module (Without ACC))

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DTC U0100  : BCM (Body Control Module) Lost Communication with ECM/PCM DTC U0122  : BCM (Body Control Module) Lost Communication with VSA/ABS

NOTE: 

DTC Description DTC
U0100 BCM (Body Control Module) lost communication with ECM/PCM  
U0122 BCM (Body Control Module) lost communication with VSA/ABS  

DTC (Body Control Module)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Wait for at least 6 seconds.

    -4. Check for DTCs with the HDS.

    DTC Description DTC
    U0100 BCM (Body Control Module) lost communication with ECM/PCM  
    U0122 BCM (Body Control Module) lost communication with VSA/ABS  

    Are any DTCs indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for loose or poor connections.

  2. Open wire check (F-CAN A_H line, F-CAN A_L line)

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

    -2. Disconnect the receiving control unit connector.

    Body control module connector A (66P)

    -3. U0100: Jump the SCS line with the HDS, and wait more than 1 minute.

    SCS short

    -4. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

    DTC Connector
    U0100 PCM connector A (50P)
    U0122 VSA modulator-control unit 46P connector

    -5. Check for continuity between the receiving control unit and the transmitting control unit on the F-CAN A_H circuit and the F-CAN A_L circuit.

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector A (66P): disconnected
    Transmitting control unit connector (s) for indicated DTCs: disconnected
    DTC Circuit name Receiving control unit Transmitting control unit
    Connector Terminal Connector Terminal
    U0100 F-CAN A_H Body control module connector A (66P) No. 64 PCM connector A (50P) No. 37
    F-CAN A_L No. 63 No. 36
    U0122 F-CAN A_H Body control module connector A (66P) No. 64 VSA modulator-control unit 46P connector No. 20
    F-CAN A_L No. 63 No. 21

    Is there continuity?

    YES 

    The F-CAN A_H wire and the F-CAN A_L wire are OK. Go to step 3.

    NO 

    Repair an open in the F-CAN A_H wire and/or the F-CAN A_L wire between the body control module and the transmitting control unit.

  3. Determine possible failure area (the receiving control unit or the transmitting control unit)

    -1. Reconnect all the connectors.

    -2. Clear the DTCs with the HDS.

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

    -4. Wait for at least 6 seconds.

    -5. Check the DTCs with the HDS.

    DTC Description DTC
    U0100 BCM (Body Control Module) lost communication with ECM/PCM  
    DTC Description DTC
    U0122 BCM (Body Control Module) lost communication with VSA/ABS  

    Are both DTCs indicated?

    YES 

    Check for loose terminals and poor connections in the body control module connectors. If they are OK, replace the body control module .

    NO 

    The body control module is OK at this time. Refer to the DTC shown on the display, then substitute or replace the control unit based on the instructions (see table).

    DTC Operation for transmitting control unit
    U0100 Substitute a known-good PCM , then recheck. If DTC U0100 goes away after substitution, replace the original PCM .
    U0122 Replace the VSA modulator-control unit .