Toyota RAV4 (XA40) 2013-2018 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 e37 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 ...
Solar sensor circuit (driver side)
Description
The solar sensor, which is installed on the upper side of the instrument
panel, detects sunlight and
controls the air conditioning auto mode. The output voltage from the solar
se ...
Other materials:
Engine control system malfunction
Description
If a malfunction in the engine control system is detected, the operations of
vsc and trc are prohibited
by the fail-safe function. When the signals from the engine are input normally,
the fail-safe is canceled and
the dtc is not stored.
Inspection procedure
Check harn ...
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 ...
Seat heaters
Turns on the front left seat
heater (high)
Turns on the front left seat
heater (low)
Turns on the front right seat
heater (high)
Turns on the front right seat
heater (low)
The indicator light comes on.
The seat heaters can be used when
Vehicles without a smart key system
T ...
