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Drive Mode Select Switch Circuit [11/2017 - ]: Procedure

  1. CHECK THE PROBLEM SYMPTOMS 
    1. Check each symptom by checking the suspected areas in the table below.

      Result

      Result Proceed to
      SPORT, SPORT S/S+ mode or NORMAL mode is abnormal. A
      ECO mode is abnormal. B

    Result: 

    B 

    GO TO AIR CONDITIONING SYSTEM. Refer to  ECO Switch Circuit [11/2017 - ] 

    Result: 

    A 

    See step  2

  2. CHECK CAN COMMUNICATION SYSTEM 
    1. Check for DTCs.

      Refer to DIAGNOSIS SYSTEM [11/2017 - 10/2018] , or refer to DIAGNOSIS SYSTEM [10/2018 - 11/2019] , or refer to DIAGNOSIS SYSTEM [11/2019 - 09/2020] , or refer to DIAGNOSIS SYSTEM [09/2020 - 10/2022] , or refer to DIAGNOSIS SYSTEM [10/2022 - 10/2023] , or refer to DIAGNOSIS SYSTEM [10/2023 - ]

      Result

      Result Proceed to
      CAN communication system DTCs are not output. A
      CAN communication system DTCs are output. B

    Result: 

    B 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ] 

    Result: 

    A 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) - BODY GROUND) 
    1. Turn the engine switch off.
    2. Disconnect the O78 drive mode select switch (combination switch assembly) connector.
      GTY505103Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Drive mode select switch (combination switch assembly))
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O78-16 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) 
    1. Inspect drive mode select switch (combination switch assembly).

      for A760H: Refer to INSPECTION [11/2017 - 09/2020] , or refer to INSPECTION [09/2020 - ]

      for AA81E: Refer to INSPECTION [11/2017 - 09/2020] , or refer to INSPECTION [09/2020 - ]

      OK

      Drive mode select switch (combination switch assembly) is normal.

      Result

      Result Proceed to
      CAN communication system DTCs are not output. (for 2GR-FKS) A
      CAN communication system DTCs are not output. (for 8AR-FTS) B
      CAN communication system DTCs are output. C

    Result: 

    B 

    See step  6

    Result: 

    C 

    REPLACE COMBINATION SWITCH ASSEMBLY 

    for A760H: Refer to REMOVAL [09/2014 - ]

    for AA81E: Refer to REMOVAL [09/2014 - ]

    Result: 

    A 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) - ECM) 
    1. Reconnect the O78 drive mode select switch (combination switch assembly) connector.
    2. Disconnect the A91 ECM connectors.
      GTY795148Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to ECM)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      W/ ADAPTIVE VARIABLE SUSPENSION SYSTEM

      Tester Connection Condition Specified Condition
      A91-55 (PWMS) - Body ground SPORT S/S+ mode switch being turned and held Below 50 Ω
      A91-55 (PWMS) - Body ground SPORT S/S+ mode switch not turned 10 kΩ or higher
      A91-40 (SPCN) - Body ground NORMAL/CUSTOM mode switch being pushed and held Below 50 Ω
      A91-40 (SPCN) - Body ground NORMAL/CUSTOM mode switch not pushed 10 kΩ or higher
      W/O ADAPTIVE VARIABLE SUSPENSION SYSTEM

      Tester Connection Condition Specified Condition
      A91-55 (PWMS) - Body ground SPORT mode switch being turned and held Below 50 Ω
      A91-55 (PWMS) - Body ground SPORT mode switch not turned 10 kΩ or higher
      A91-40 (SPCN) - Body ground NORMAL mode switch being pushed and held Below 50 Ω
      A91-40 (SPCN) - Body ground NORMAL mode switch not pushed 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2017 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. CHECK HARNESS AND CONNECTOR (DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) - ECM) 
    1. Reconnect the O78 drive mode select switch (combination switch assembly) connector.
    2. Disconnect the A82 ECM connectors.
      GTY790085Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to ECM)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      W/ ADAPTIVE VARIABLE SUSPENSION SYSTEM

      Tester Connection Condition Specified Condition
      A82-36 (PWMS) - Body ground SPORT S/S+ mode switch being turned and held Below 50 Ω
      A82-36 (PWMS) - Body ground SPORT S/S+ mode switch not turned 10 kΩ or higher
      A82-39 (SPCN) - Body ground NORMAL/CUSTOM mode switch being pushed and held Below 50 Ω
      A82-39 (SPCN) - Body ground NORMAL/CUSTOM mode switch not pushed 10 kΩ or higher
      W/O ADAPTIVE VARIABLE SUSPENSION SYSTEM

      Tester Connection Condition Specified Condition
      A82-36 (PWMS) - Body ground SPORT mode switch being turned and held Below 50 Ω
      A82-36 (PWMS) - Body ground SPORT mode switch not turned 10 kΩ or higher
      A82-39 (SPCN) - Body ground NORMAL mode switch being pushed and held Below 50 Ω
      A82-39 (SPCN) - Body ground NORMAL mode switch not pushed 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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