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DTC U0233: Lost Communication with Blind Spot Monitor Master Module [06/2014 - 10/2016]: Procedure

  1. RECONFIRM DTC OUTPUT 

    Body Electrical > Gateway > Trouble Codes 

    1. Reconfirm DTCs.

      HINT: 

      If DTC U1002 is output from Gateway of the network gateway ECU, this indicates a sub bus 2 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 2.

      Result

      Result Proceed to
      DTC U1002 is not output from network gateway ECU (Techstream display: Gateway) A
      DTC U1002 is output from network gateway ECU (Techstream display: Gateway) B

    Result: 

    B 

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DTC U1002: Lost Communication with Gateway Module (Network Gateway ECU) [06/2014 - 10/2016] 

    Result: 

    A 

    See step  2

  2. CHECK FOR OPEN IN SUB BUS 2 LINES (BLIND SPOT MONITOR SENSOR LH BRANCH LINE) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the Q50 blind spot monitor sensor LH connector.
      GTY460258Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Blind Spot Monitor Sensor LH)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q50-2 (CA1P) - Q50-7 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Result

      Result
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (BLIND SPOT MONITOR SENSOR LH) 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) 
    1. Measure the resistance according to the value(s) in the table below.
      GTY460261Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Blind Spot Monitor Sensor LH)

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q50-10 (BLGD) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
    2. Reconnect the cable to the negative (-) battery terminal.
    3. Measure the voltage according to the value(s) in the table below.
      GTY460262Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Blind Spot Monitor Sensor LH)

      Standard Voltage

      Tester Connection Condition Specified Condition
      Q50-5 (BLB) - Body ground Engine switch on (IG) 11 to 14 V

      Result

      Result
      OK
      NG

    Result: 

    OK 

    REPLACE BLIND SPOT MONITOR SENSOR LH. Refer to  REMOVAL [04/2013 - 10/2016] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

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