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Inspection Procedure

HINT:

Start the engine before inspection. Check the IG1 relay or battery if the engine does not start.

  1. INSPECT FUSE (ECU-IG RH) 
    1. Remove the ECU-IG RH fuse from the cowl side junction block RH.
    2. Measure the resistance of the fuse.

    Standard resistance 

    RESISTANCE SPECIFICATION

    Tester Item Condition Specified Condition
    ECU-IG RH fuse Always Below 1 Ω

    NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE 

    OK: Go to next step 

  2. INSPECT AIR CONDITIONING AMPLIFIER (IG+ - GND) 
    1. Remove the A/C amplifier with its connectors still connected.
    2. Turn the engine switch on (IG).
    3. Measure the voltage of the connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      K52-21 (IG+) - K52-20 (GND) Engine switch on (IG) 10 to 14 V
    Fig 1: Identifying Air Conditioning Amplifier Connector Terminals
    G05297803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG:  Go to step  3

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

  3. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY) 
    1. Disconnect the K52 A/C amplifier connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      KS2-21 (IG+) - Body ground Engine switch off Below 1.0 V
      Engine switch on (IG) 10 to 14 V
    Fig 2: Identifying Air Conditioning Amplifier Connector Terminal
    G05297804Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  4. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND) 
    1. Disconnect the K52 A/C amplifier connector.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      K52-20 (GND) - Body ground Always Below 1 Ω
    Fig 3: Identifying Air Conditioning Amplifier Connector Terminal
    G05297805Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: REPLACE AIR CONDITIONING AMPLIFIER 

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