Toyota RAV4 Service Manual: Ig power source circuit
Description
This is the main power source supplied to the air conditioning amplifier when the ignition switch is on.
This power source is used for operating components, such as the air conditioning amplifier and servo motors.
Wiring diagram
Inspection procedure
- Inspect fuse (ecu-ig2)
- Remove the ecu-ig2 fuse from the instrument panel junction block.
- Measure the resistance of the fuse.
Standard resistance:
below 1 
- Check wire harness (air conditioning amplifier - battery)
- Disconnect the e36 amplifier connector.
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Check wire harness (air conditioning amplifier - body ground)
- Disconnect the e36 amplifier connector.
- Measure the resistance of the wire harness side connector.
Standard resistance 
Proceed to next circuit inspection shown in problem symptoms table
Compressor circuit
Description
When the a/c switch is turned on, the magnetic clutch on signal is sent from
the air conditioning
amplifier. Then the mg clt relay turns on to operate the magnetic clutch.
Wiring diag ...
Refrigerant
...
Other materials:
Components
...
Engine coolant temperature circuit
Description
A thermistor, whose resistance value varies according to the ect, is built
into the engine coolant
temperature (ect) sensor.
The structure of the sensor and its connection to the ecm are the same as those
of the intake air
temperature (iat) sensor.
Hint:
When any of dtcs ...
Using the automatic air conditioning system
Press .
The dehumidification function begins to operate. Air outlets and fan speed
are automatically adjusted according to the temperature setting and
humidity.
Turn clockwise to
increases the temperature and turn
counterclockwise to decreases
the temperature.
T ...