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DTC B2275: STSW Monitor Malfunction [10/2018 - ]: Procedure

  1. CHECK FOR DTC 
    1. Turn the power switch on (IG) and wait 25 seconds.
    2. Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.

      Body Electrical > Power Source Control > Trouble Codes 

      OK

      DTC B2285 is not output simultaneously.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO DTC B2285. Refer to  DTC B2285: Steering Lock Position Signal Circuit Malfunction [10/2018 - 07/2022]  Refer to  DTC B2285: Steering Lock Position Signal Circuit Malfunction [07/2022 - ]  

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - HYBRID VEHICLE CONTROL ECU) 
    1. Disconnect the F44 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F59 hybrid vehicle control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F44-27 (ST2) - F59-4 (ST2) Always Below 1 Ω
      F44-27 (ST2) or F59-4 (ST2) - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Reconnect the F44 certification ECU (smart key ECU assembly) connector.
    2. Reconnect the F59 hybrid vehicle control ECU connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F44-27 (ST2) - Body ground With the brake pedal depressed, the power switch is pressed and held → After approx. 3 sec. has elapsed, the power switch is released 8.5 V or higher → 1 V or less

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU. Refer to  REMOVAL [10/2018 - 07/2022]  Refer to  REMOVAL [07/2022 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2018 - 07/2022]  Refer to  REMOVAL [07/2022 - ]