Toyota RAV4 (XA40) 2013-2018 Service Manual: Ambient temperature sensor circuit
Description
The ambient temperature sensor is installed in the front part of the condenser to detect the ambient temperature and control the air conditioner. The sensor is connected to the combination meter and detects fluctuations in the ambient temperature. This data is used for controlling the room temperature.
The sensor sends a signal to the air conditioning amplifier via the combination meter. The resistance of the ambient temperature sensor changes in accordance with the ambient temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The air conditioning amplifier applies a voltage (5 v) to the ambient temperature sensor and reads voltage changes as changes in the resistance of the ambient temperature sensor. The combination meter sends the read signal to the air conditioning amplifier via can communication.
Wiring diagram
Inspection procedure
- Read value of intelligent tester (ambi temp sens)
- Connect the intelligent tester (with can vim) to the dlc3.
- Turn the ignition switch on and turn the intelligent tester main switch on.
- Select the item below in the data list, and read the value displayed on the intelligent tester.
Ok: the display is as specified in the normal condition column.
- Inspect ambient temperature sensor
- Remove the ambient temperature sensor.
- Measure the resistance of the sensor.
Standard resistance 
Notice:
- 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 the graph).
- Check wire harness (ambient temperature sensor - combination meter)
- Disconnect the a17 sensor connector.
- Disconnect the e19 meter connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
Replace combination meter
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Description
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the room temperature and
control the heater and air conditioner auto mode. The resistance of the room
t ...
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Description
The no. 1 Cooler thermistor (evaporator temperature sensor) is installed on
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Other materials:
Refrigerant line
Components (2005/11-2006/01)
Components (2006/01- )
...
Dtc check / clear
Check dtc
Dtcs which are stored in the ecm can be displayed
with the intelligent tester.
The intelligent tester can display pending dtcs and
current dtcs. Some dtcs are not stored unless a
malfunction is detected in consecutive driving
cycles. When a malfunction is detected ...
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Description
The skid control ecu detects the brake operating conditions through a signal
transmitted by the stop light
switch. The skid control ecu incorporates an open circuit detection circuit.
This dtc is set under either of
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An open is detected in the stop lig ...
