Toyota RAV4 Service Manual: Pressure sensor circuit
Description
This dtc is output when the refrigerant pressure is either extremely low (0.19 Mpa [2.0 Kgf/cm2, 28 psi] or less) or extremely high (3.14 Mpa [32.0 Kgf/cm2, 455 psi] or more). The air conditioning pressure sensor, which is installed on the pipe of the high pressure side, detects the refrigerant pressure and sends refrigerant pressure signals to the air conditioning amplifier. The air conditioning amplifier determines the pressure from the signals in accordance with the sensor characteristics, and controls the compressor accordingly.
Wiring diagram
Inspection procedure
- Check refrigerant
- Check the sight glass of the cooler unit refrigerant liquid pipe.
- Prepare the vehicle in accordance with the chart
below.
- Compare the sight glass to the following chart.
Hint:
*: If the ambient temperature is higher than usual but cooling is sufficient, bubbles in the sight glass are permissible.
- Read value of intelligent tester (reg press 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.
- Check wire harness (pressure sensor - air conditioning amplifier)
- Disconnect the a21 pressure sensor connector.
- Disconnect the e36 amplifier connector.
- measure the resistance of the wire harness side connectors.
Standard resistance 
- Check air conditioning amplifier
- Remove the air conditioning amplifier with its connectors still connected.
- Measure the resistance of the wire harness side connector
Standard resistance 
- Turn the ignition switch on.
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Inspect air conditioning pressure sensor
- Turn the a/c switch on.
- Disconnect the a21 sensor connector.
- Connect the three 1.5 V dry cell batteries' positive (+)
lead to terminal 3 and the negative (-) lead to terminal 1.
Then connect the voltmeter's positive (+) lead to terminal 2 and the negative (-) lead to terminal 1. Measure the voltage.
Ok: the voltage changes in accordance with the refrigerant pressure as shown in the graph.
Replace air conditioning amplifier
Compressor lock sensor circuit
Description
This sensor sends 1 pulse per engine revolution to the air conditioning
amplifier. If the ratio of the
compressor speed divided by the engine speed is smaller than a predetermined ...
Compressor solenoid circuit (2005/11-2006/01)
Description
In this circuit, the compressor receives a refrigerant compression demand
signal from the air conditioning
amplifier. Based on this signal, the compressor changes the degree of
r ...
Other materials:
Srs airbags
The srs airbags inflate when the vehicle is subjected to certain
types of severe impacts that may cause significant injury to the
occupants. They work together with the seat belts to help reduce
the risk of death or serious injury.
Srs front airbags
Srs driver airbag/front passenger airb ...
Diagnosis system
Description
Key reminder warning system data can be read
through the data link connector 3 (dlc3) of the
vehicle. When the system seems to be
malfunctioning, use the intelligent tester (with can
vim) to check for malfunctions and perform repairs.
Check dlc3
The vehi ...
Room temperature sensor (for automatic ai conditioning system)
Components
Removal
Remove lower instrument panel
Remove the lower instrument panel (see page ip-
16).
Remove room temperature sensor
Disconnect the duct.
Disconnect the connector.
Detach the claws and remove the sensor.
Inspection
Inspect room temperature ...