Toyota RAV4 manuals

Toyota RAV4 Service Manual: Pressure sensor circuit

Toyota RAV4. 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.

Toyota RAV4. Pressure sensor circuit


Wiring diagram

Toyota RAV4. Pressure sensor circuit


Inspection procedure

  1. Check refrigerant

Toyota RAV4. Check refrigerant


  1. Check the sight glass of the cooler unit refrigerant liquid pipe.
  1. Prepare the vehicle in accordance with the chart below.

  1. Compare the sight glass to the following chart.

Toyota RAV4. Check refrigerant


Hint:

*: If the ambient temperature is higher than usual but cooling is sufficient, bubbles in the sight glass are permissible.



  1. Read value of intelligent tester (reg press sens)

  1. Connect the intelligent tester (with can vim) to the dlc3.
  2. Turn the ignition switch on and turn the intelligent tester main switch on.
  3. Select the item below in the data list, and read the value displayed on the intelligent tester.

Toyota RAV4. Read value of intelligent tester (reg press sens)


Ok: the display is as specified in the normal condition column.

Toyota RAV4. Read value of intelligent tester (reg press sens)




  1. Check wire harness (pressure sensor - air conditioning amplifier)

Toyota RAV4. Check wire harness (pressure sensor - air conditioning amplifier)


  1. Disconnect the a21 pressure sensor connector.
  2. Disconnect the e36 amplifier connector.
  3. measure the resistance of the wire harness side connectors.

Standard resistance




  1. Check air conditioning amplifier

Toyota RAV4. Check air conditioning amplifier


  1. Remove the air conditioning amplifier with its connectors still connected.
  2. Measure the resistance of the wire harness side connector

Standard resistance


  1. Turn the ignition switch on.
  2. Measure the voltage of the wire harness side connector.

Standard voltage




  1. Inspect air conditioning pressure sensor

  1. Turn the a/c switch on.
  2. Disconnect the a21 sensor connector.
  3. 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.

Toyota RAV4. Inspect air conditioning pressure sensor




Replace air conditioning amplifier

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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:

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 conditioni ...

Diagnosis system
Description Air conditioning system data and the diagnostic trouble codes (dtcs) can be read through the data link connector 3 (dlc3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform troubleshooting. ...

Pressure control solenoid "B" performance (shift solenoid valve sl2)
Description The ecm uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd or o/d gear). Then the ecm compares the actual gear with the shift schedule in the ecm memory to detect mechanical problems of the shift solenoid ...

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