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Inspection Procedure

  1. CHECK MULTIPLEX COMMUNICATION SYSTEM 
    1. Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally.

      Result 

      DTC RESULT DESCRIPTION

      Result Proceed to
      MPX DTC is not output A
      MPX DTC is output B

    B:  GO TO MULTIPLEX COMMUNICATION SYSTEM

    A: Go to Next Step 

  2. CHECK CAN COMMUNICATION SYSTEM 
    1. Use the Techstream to check if the CAN Communication System is functioning normally.

      Result 

      DTC RESULT DESCRIPTION

      Result Proceed to
      CAN DTC is not output A
      CAN DTC is output B

    B:  GO TO CAN COMMUNICATION SYSTEM

    A: Go to Next Step 

  3. INSPECT ECM 
    1. Remove the ECM with its connectors still connected.
    2. Measure the waveform of the connector.

      Standard 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      E3-10 (LCKI) - Body ground Engine switch on (IG) AUTO switch ON A/C switch ON Magnetic clutch ON Pulse generation
      ITEM DESCRIPTION

      Item Contents
      Tool setting 200 mV/DIV., 10 ms/DIV.
      Vehicle condition Engine switch on (IG)
      AUTO switch ON
      A/C switch ON
      Magnetic clutch ON
      Fig 1: Identifying ECM Connector Terminals And Waveform Graph
      G05831411Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      DTC RESULT DESCRIPTION

      Result Proceed to
      NG A
      OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE) B
      OK (When troubleshooting according to the DTC) C

    B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

    C: REPLACE ECM 

    A: Go to Next Step 

  4. INSPECT A/C COMPRESSOR (LOCK SENSOR) 
    1. Disconnect the A/C compressor connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      E8-2 (SSR+) - E8-S (SSR-) 160 to 320 Ω
      3. Fig 2: Identifying A/C Compressor Connector Terminals
      G05831412Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE A/C COMPRESSOR (LOCK SENSOR) 

    OK: Go to Next Step 

  5. CHECK WIRE HARNESS (ECM - A/C COMPRESSOR) 
    1. Disconnect the A/C compressor connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      E3-10 (LCKI) - E8-2 (SSR+) Always Below 1 Ω
      E3-10 (LCKI) - Body ground Always 10 kΩ or higher
      E8-5 (SSR-) - Body ground Always Below 1 Ω
      4. Fig 3: Disconnecting ECM Connector
      G05831413Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM 

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