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DTC U0122: Lost Communication with Vehicle Stability Control Module; DTC U0129: Lost Communication with Brake System Control Module [09/2014 - 10/2015]: Procedure

  1. RECONFIRM DTC OUTPUT 
    1. Reconfirm DTCs.

      HINT: 

      If DTC U1002 is output from Gateway of the network gateway ECU, this indicates a sub bus 19 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 19.

      RESULT

      Result Proceed to
      DTC U1002 is not output from network gateway ECU. A
      DTC U1002 is not output from network gateway ECU. B

    Result:  B

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC 

    (See service information). Refer to DTC U1002: Lost Communication with Gateway Module [09/2014 - 10/2015] )

    Result:  A

    See step  2

  2. RECONFIRM DTC OUTPUT 
    1. Reconfirm DTCs.

      HINT: 

      If DTC U1107-436 is output from Gateway of the power management control ECU, this indicates a sub bus 15 malfunction. Troubleshoot for DTC U1107-436 and check for malfunctions in sub bus 15.

      RESULT

      Result Proceed to
      DTC U1107-436 is not output from power management control ECU. A
      DTC U1107-436 is not output from power management control ECU. B

    Result:  B

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC 

    (See service information). Refer to DTC U1107-436: Lost Communication with Power Management Module [09/2014 - 10/2015] )

    Result:  A

    See step  3

  3. CHECK FOR OPEN IN CAN BUS WIRE (SKID CONTROL ECU ASSEMBLY CAN MAIN AND CAN BRANCH WIRE) 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
      GTY524139Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the skid control ECU assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      SUB BUS 19

      Tester Connection Condition Specified Condition
      A14-7 (CA2H) - A14-6 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      SUB BUS 15

      Tester Connection Condition Specified Condition
      A16-9 (CANH) - A16-8 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *A Sub Bus 19
      *B Sub Bus 15
      *a Front view of wire harness connector
      (to Skid Control ECU Assembly)
      RESULT

      Result Proceed to
      OK A
      NG (Sub Bus 19) B
      NG (Sub Bus 15) C

    Result:  B

    REPAIR OR REPLACE SKID CONTROL ECU ASSEMBLY CAN MAIN WIRE OR CONNECTOR (CA2H, CA2L) 

    Result:  C

    REPAIR OR REPLACE SKID CONTROL ECU ASSEMBLY CAN BRANCH WIRE OR CONNECTOR (CANH, CANL) 

    Result:  A

    See step  4

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU ASSEMBLY - BATTERY AND BODY GROUND) 
    1. Connect the cable to the negative (-) auxiliary battery terminal.
      GTY530203Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      When connecting the cable, some systems need to be initialized after the cable is reconnected (See service information). Refer to INITIALIZATION [09/2014 - 10/2015] ).

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A14-43 (+BI1) - Body ground Always 11 to 14 V
      A14-29 (+BI3) - Body ground Always 11 to 14 V
      A16-38 (+BI2) - Body ground Always 11 to 14 V
      A16-22 (+BI4) - Body ground Always 11 to 14 V
      A14-46 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      A16-46 (IG2) - Body ground Power switch on (IG) 11 to 14 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A14-1 (GND) - Body ground Always Below 1 Ω
      A16-1 (GND4) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU Assembly)

    Result:  OK

    OK 

    REPLACE SKID CONTROL ECU ASSEMBLY 

    (See service information). Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR