Toyota RAV4 (XA40) 2013-2018 Service Manual: Evaporator temperature sensor circuit
Description
The no. 1 Cooler thermistor (evaporator temperature sensor) is installed on the evaporator in the air conditioning unit to detect the temperature of the cooled air that has passed through the evaporator and to control the air conditioner. It sends signals to the air conditioning amplifier. The signals change in accordance with the resistance of the no. 1 Cooler thermistor (evaporator temperature sensor). 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 no. 1 Cooler thermistor (evaporator temperature sensor) and reads voltage changes as changes in the resistance of the no. 1 Cooler thermistor (evaporator temperature sensor). This sensor is used for frost prevention.
Wiring diagram
Inspection procedure
- Read value of intelligent tester (evap fin temp)
- 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 no. 1 Cooler thermistor (evaporator temperature sensor)
- Remove the no. 1 Cooler thermistor.
- Measure the resistance of the thermistor.
Standard resistance
Notice:
- Touching the thermistor even slightly may change the resistance value. Be sure to hold the connector of the thermistor.
- When measuring, the thermistor temperature must be the same as the ambient temperature.
Hint:
As the temperature increases, the resistance decreases (see the graph).
- Check wire harness (no. 1 Cooler thermistor - air conditioning amplifier)
- Disconnect the e33 no. 1 Cooler thermistor connector.
- Disconnect the e36 amplifier connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
Replace air conditioning amplifier
Ambient temperature sensor circuit
Description
The ambient temperature sensor is installed in the front part of the
condenser to detect the ambient
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c ...
Compressor lock sensor circuit
Description
This sensor sends 1 pulse per engine revolution to the air conditioning
amplifier. If the ratio of the
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Other materials:
Snow mode switch (AWD
vehicles)
Snow mode can be selected
to suit the conditions when
driving on slippery road surfaces,
such as on snow.
System operation
â– Dynamic Torque Control
AWD vehicles
Press the snow mode switch.
When the switch is pressed, the
system switches to snow mode and
the snow mode indicator illuminates
on the ...
System description
Engine immobiliser system description
The engine immobiliser system is designed to prevent
the vehicle from being stolen. This system uses a
transponder key ecu that stores the key codes of
authorized ignition keys. If an attempt is made to start
the engine using an unauthorized key, the e ...
Radiator
Components
On-vehicle inspection
Check radiator reservoir cap subassembly
Measure the valve opening pressure.
If there are water stains or foreign matter on oring
1, clean it with water and finger scouring.
Check that o-ring 1 is not deformed, cracked or
sw ...
