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Inspection Procedure

WARNING: This page is about a different car, the 2007 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE OF INTELLIGENT TESTER (AMBI TEMP SENS) 
    1. Connect the intelligent tester (with CAN VIM) to the DLC3.
    2. Turn the ignition switch ON and turn the intelligent tester main switch ON.
    3. Select the item below in the DATA LIST, and read the value displayed on the intelligent tester.

      Air conditioning amplifier 

      DATA LIST DETAIL

      Item Measurement Item / Display (Range) Normal Condition Diagnostic Note
      AMBI TEMP SENS Ambient temperature sensor /
      Min.: -23.3°C (-9.94°F)
      Max.: 65.95°C (150.71°F)
      Actual ambient temperature is displayed Open circuit: -23.3°C (-9.94°F)
      Short circuit: 65.95°C (150.71°F)

      OK : 

      The display is as specified in the normal condition column. 

      Result 

      RESULT REFERENCE

      Result Proceed to
      NG A
      OK (Checking from the PROBLEM SYMPTOMS TABLE)
       
      B
      OK (Checking from the DTC) C

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

    C: REPLACE AIR CONDITIONING AMPLIFIER 

    A: GO TO NEXT STEP. 

  2. INSPECT AMBIENT TEMPERATURE SENSOR 
    1. Remove the ambient temperature sensor (see Fig 1).
    2. Measure the resistance of the sensor.

      Standard resistance 

      TERMINALS RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      1 - 2 10°C (50°F) 3.00 to 3.73 k
      1 - 2 15°C (50°F) 2.45 to 2.88 k
      1 - 2 20°C (68°F) 1.95 to 2.30 k
      1 - 2 25°C (77°F) 1.60 to 1.80 k
      1 - 2 30°C (86°F) 1.28 to 1.47 k
      1 - 2 35°C (95°F) 1.00 to 1.22 k
      1 - 2 40°C (104°F) 0.80 to 1.00 k
      1 - 2 45°C (113°F) 0.65 to 0.85 k
      1 - 2 50°C (122°F) 0.50 to 0.70 k
      1 - 2 55°C (131°F) 0.44 to 0.60 k
      1 - 2 60°C (140°F) 0.36 to 0.50 k
      NOTE:
      • Touching the sensor even slightly may change the resistance value. Be sure to hold the connector of the sensor.
      • When measuring, the sensor temperature must be the same as the ambient temperature.

      HINT:

      As the temperature increases, the resistance decreases (see Fig 1).

      Fig 1: Ambient Temperature Sensor Resistance Graph
      G04489900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE AMBIENT TEMPERATURE SENSOR 

    OK: GO TO NEXT STEP. 

  3. CHECK WIRE HARNESS (AMBIENT TEMPERATURE SENSOR - COMBINATION METER) 
    1. Disconnect the A17 sensor connector.
    2. Disconnect the E19 meter connector.
      Fig 2: Identifying A17 & E19 Connectors
      G04489901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TERMINALS RESISTANCE SPECIFICATION (CONNECTOR(S) DISCONNECTED)

      Tester Connection Specified Condition
      A17-2 (OT+) - E19-23 (TEMP) Below 1
      A17-1 (OT-) - E19-11 (TX1+) Below 1
      A17-2 (OT+) - Body ground 1 M or higher
      A17-1 (OT-) - Body ground 1 M or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: GO TO NEXT STEP. 

    REPLACE COMBINATION METER