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Room Temperature Sensor: Inspection

  1. INSPECT ROOM TEMPERATURE SENSOR 
    1. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      J38-1 - J38-2 10°C (50°F) 3.00 to 3.73 kΩ
      J38-1 - J38-2 15°C (59°F) 2.45 to 2.88 kΩ
      J38-1 - J38-2 20°C (68°F) 1.95 to 2.30 kΩ
      J38-1 - J38-2 25°C (77°F) 1.60 to 1.80 kΩ
      J38-1 - J38-2 30°C (86°F) 1.28 to 1.47 kΩ
      J38-1 - J38-2 35°C (95°F) 1.00 to 1.22 kΩ
      J38-1 - J38-2 40°C (104°F) 0.80 to 1.00 kΩ
      J38-1 - J38-2 45°C (113°F) 0.65 to 0.85 kΩ
      J38-1 - J38-2 50°C (122°F) 0.50 to 0.70 kΩ
      J38-1 - J38-2 55°C (131°F) 0.44 to 0.60 kΩ
      J38-1 - J38-2 60°C (140°F) 0.36 to 0.50 kΩ
      NOTE:
      • Hold the sensor only by its connector. Touching the sensor may change the resistance value.
      • When measuring, the sensor temperature must be the same as the ambient temperature.

      HINT:

      As the temperature increases, the resistance decreases (see the graph below).

      If the resistance is not as specified, replace the room temperature sensor.

      Fig 1: Identifying A/C Room Temperature Sensor Connector Terminals And Graph
      G05831392Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002