LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2020 >> GX 460 Base >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Air Conditioning System (Service Information) >> Refrigerant >> Replacement [08/2020 - ] >> Procedure

Replacement [08/2020 - ]: Procedure

  1. RECOVER REFRIGERANT FROM REFRIGERATION SYSTEM 
    1. Start the engine.
    2. Turn the A/C switch on.
    3. Operate the compressor under the following conditions:
      Item Condition
      Operating time 3 minutes or more
      Temperature setting Max cold
      Blower speed High
      Engine Idling
      A/C switch On

      This causes most of the compressor oil from the various components of the A/C system to collect in the compressor.

      HINT: 

      It is not necessary to operate the compressor if the A/C does not operate because of compressor lock, etc.

    4. Stop the engine.
    5. Recover the refrigerant from the A/C system using a refrigerant recovery unit.

      HINT: 

      Use the refrigerant recovery unit in accordance with the manufacturer's instruction service information.

  2. CHARGE REFRIGERANT 

    HINT: 

    Charge the system with refrigerant in accordance with the manufacturer's instruction service information.

    1. Perform vacuum purging using a vacuum pump or appropriate equipment.
      NOTE:

      Be sure to use a refrigerant recovery unit that is compatible with HFO-1234yf (R1234yf) systems.

    2. Charge the air conditioning system with refrigerant.

      Refrigerant Type

      HFO-1234yf (R1234yf)

      GTY454611Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Standard Charge Amount *b Mean Value in Proper Range
      *c Overcharged *d High Pressure
      *e Sub-cool System *f Refrigerant Amount
      *g +/-30 g (+/-1.05 oz) - -

      Standard charge amount

      w/o Rear Cooler, Cool Box 

      520 to 580 g (18.3 to 20.4 oz)

      w/ Rear Cooler, w/o Cool Box 

      770 to 830 g (27.2 to 29.2 oz)

      w/ Rear Cooler, Cool Box 

      840 to 900 g (29.7 to 31.7 oz)

      NOTE:
      • Make sure that the amount of refrigerant is within 30 g (1.1 oz) of the specified amount.
      • Do not turn the A/C switch on before charging the air conditioning system with refrigerant. Doing so may cause the compressor to work without refrigerant, resulting in overheating of the compressor.
      • The refrigerant amount should be checked by quantity (weight).
      • The graph above is shown for reference only.

      HINT: 

      Ensure that sufficient refrigerant is available to recharge the system when using a refrigerant recovery unit. Refrigerant recovery units are not always able to recover 100% of the refrigerant from an air conditioning system.

  3. WARM UP ENGINE 
    1. Warm up the engine at less than 1850 rpm for 2 minutes or more after charging the refrigerant.
      NOTE:

      Be sure to warm up the compressor by turning the A/C switch is on after removing and installing the cooler refrigerant lines (including the compressor) to prevent damage to the compressor.

  4. CHECK FOR REFRIGERANT GAS LEAK 
    1. After recharging the air conditioning system with refrigerant, inspect for refrigerant leaks using a gas leak detector.
    2. Carry out the test under the following conditions:
      • Turn the ignition switch off.
      • Ensure good ventilation (the gas leak detector may react to volatile gases which are not refrigerant, such as gasoline vapor and exhaust gas).
      • Repeat the inspection 2 or 3 times.
      • Measure the pressure to make sure that there is some refrigerant remaining in the air conditioning system.

        Pressure when the compressor is off: approximately 392 to 588 kPa (3.9 to 5.9 kgf/cm2 , 57 to 85 psi).

    3. Using a gas leak detector, inspect for refrigerant leaks from the air conditioning system.
      GTY372096Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Inspect for Leak
      *b Gas Leak Detector