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ECO Switch Circuit [11/2021 - ]: Procedure

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  1. READ VALUE USING GTS (ECO SWITCH) 
    1. Read the Data List according to the display on the GTS.

      Body Electrical > Air Conditioner > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      ECO Switch ECO switch (combination switch assembly) input condition OFF or ON OFF: ECO switch (combination switch assembly) not operated
      ON: ECO switch (combination switch assembly) operated and held      		 ECO switch (combination switch assembly) circuit malfunction

      Body Electrical > Air Conditioner > Data List 

      Tester Display
      ECO Switch

      OK

      ECO switch (combination switch assembly) condition displayed on the GTS changes with the actual switch operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  2

  2. INSPECT DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) (ECO SWITCH) 

    Refer to INSPECTION [11/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (DRIVE MODE SELECT SWITCH (COMBINATION SWITCH ASSEMBLY) - AIR CONDITIONING AMPLIFIER ASSEMBLY AND BODY GROUND) 
    1. Disconnect the D33 drive mode select switch (combination switch assembly) connector.
    2. Disconnect the D52 air conditioning amplifier assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D33-5 (ECU) - D52-11 (ECOS) Always Below 1 Ω
      D33-6 (GND) - Body ground Always Below 1 Ω
      D33-5 (ECU) or D52-11 (ECOS) - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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