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DTC U0327: Software Incompatibility with Vehicle Security Control Module: Procedure

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
      WARNING:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.

      NOTE:
      • w/ Navigation System (for HDD):

        After the engine switch is turned off, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the engine switch off, be sure to wait for the time specified in the following table before disconnecting the cable from the negative (-) battery terminal.

        Waiting Time before Disconnecting Cable from Negative (-) Battery Terminal

        Condition Waiting Time
        Vehicle enrolled in safety connect system 6 minutes
        Vehicle not enrolled in safety connect system 1 minute
      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

    NEXT: Go to next step 

  2. CHECK FOR OPEN IN CAN BUS WIRE (CERTIFICATION ECU BRANCH WIRE) 
    1. Disconnect the L15 certification ECU connector.
      Fig 1: Identifying L15 Certification ECU Connector
      GTY264560Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Switch Condition Specified Condition
      L15-27 (CANH) - L15-28 (CANL) Engine switch off 54 to 69 Ω

    NG → REPAIR OR REPLACE CERTIFICATION ECU BRANCH WIRE OR CONNECTOR (CANH, CANL) 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - BATTERY AND BODY GROUND) 
    1. Connect the cable to the negative (-) battery terminal.
      NOTE:

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

    2. Disconnect the L15 certification ECU connector.
      Fig 2: Identifying L15 Certification ECU Connector Terminals
      GTY110703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      L15-17 (E) - Body ground Always Below 1 Ω
    4. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      L15-1 (+B1) - Body ground Always 11 to 14 V
      L15-20 (CUTB) - Body ground Always 11 to 14 V
      L15-18 (IG) - Body ground Engine switch on (IG) 11 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   4 

  4. REPLACE CERTIFICATION ECU. Refer to  REMOVAL