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DTC U128D (Telematics Control Unit)

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DTC U128D  : Telematics Control Unit Lost Communication with Gauge Control Module

DTC Description DTC
U128D Telematics control unit lost communication with Gauge control module  

DTCs (Telematics System)

NOTE: 

  1. Problem verification

    -1. Clear the DTCs with the HDS.

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

    -3. Open the driver's door, and wait more than 1 minute.

    -4. Turn the vehicle to the ON mode.

    -5. Wait for at least 6 seconds.

    -6. Check for DTCs with the HDS.

    DTC Description DTC
    U128D Telematics control unit lost communication with Gauge control module  

    Is DTC U128D indicated?

    YES 

    The failure is duplicated, go to step 2.

    NO 

    Intermittent failure, the system is OK at this time.

  2. Open wire check (B-CAN H line, B-CAN L line)

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

    -2. Open the driver's door, and wait more than 1 minute.

    -3. Disconnect the receiving control unit connector.

    Telematics control unit connector A (32P)

    -4. Disconnect the transmitting control unit connector (s).

    Refer to the DTC shown on the display, then disconnect the connector (s) based on the instructions (see table).

    DTC Connector
    U128D Gauge control module connector A (32P)

    -5. Check for continuity between the receiving control unit and the transmitting control unit on the B-CAN H circuit and the B-CAN L circuit.

    Test condition Vehicle OFF (LOCK) mode
      Telematics control unit connector A (32P): disconnected
      Transmitting control unit connector (s) for indicated DTCs: disconnected
    DTC Circuit name Receiving control unit Transmitting control unit
    Connector Terminal Connector Terminal
    U128D B-CAN H Telematics control unit connector A (32P) No. 22 Gauge control module connector A (32P) No. 31
    B-CAN L No. 23 No. 30

    Is there continuity?

    YES 

    The B-CAN H wire and the B-CAN L wire are OK. Refer to the DTC shown on the display, then replace the control unit based on the instructions (see chart).

    DTC Operation for transmitting control unit
    U128D Gauge control module

    NO 

    Repair an open in the B-CAN H wire and/or the B-CAN L wire.