REFRIGERANT > ON-VEHICLE INSPECTION

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1. INSPECT REFRIGERANT VOLUME


I104815

  1. Check the sight glass on the air conditioning tube.
    Test conditions:

    1. Engine running at 1500 rpm.
    2. Blower speed control switch at HI.
    3. A/C switch on.
    4. Temperature control switch is at the MAX. COLD position.
    5. All doors fully open.

    Item
    		Symptom
    		Amount of Refrigerant
    		Corrective Procedure
    1
    		Bubbles visible
    		Insufficient*
    		(1) Check for gas leakage and repair if necessary
    (2) Add refrigerant until bubbles disappear
    2
    		No bubbles visible
    		Empty, insufficient or excessive
    		Refer to items 3 and 4
    3
    		No temperature difference between compressor inlet and outlet
    		Empty or nearly empty
    		(1) Check for gas leakage with halogen leak detector and repair if necessary
    (2) Add refrigerant until bubbles disappear
    4
    		Considerable temperature difference between compressor inlet and outlet
    		Correct or excessive
    		Refer to items 5 and 6
    5
    		Immediately after A/C turned off, refrigerant becomes clear
    		Excessive
    		(1) Drain or discharge refrigerant
    (2) Bleed air and charge proper amount of purified refrigerant
    6
    		Immediately after A/C turned off, refrigerant foams and then becomes clear
    		Correct
    		-

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



2. CHECK REFRIGERANT PRESSURE USING MANIFOLD GAUGE SET


  1. This is a method to identify trouble areas by using a manifold gauge set. Read the manifold gauge pressure under the following conditions.
    Test conditions:

    1. Engine warm.
    2. All doors fully open.
    3. A/C switch on.
    4. Blower speed control switch at HI.
    5. Engine running at 1500 rpm.
    6. Air inlet mode damper set at RECIRC.
    7. Temperature control lever in MAX. COLD position.
    8. Air temperature at air inlet 30 to 35°C (86 to 95°F).



      E050573

    1. When the refrigerant volume is correct, the gauge reading indicates as follows.

      Gauge Reading:
      Pressure Side
      		Refrigerant Volume
      Low
      		0.15 to 0.25 MPa (1.5 to 2.5 kgf/cm2, 22 to 36 psi)
      High
      		1.37 to 1.57 MPa (14 to 16 kgf/cm2, 199 to 228 psi)

      HINT:
      Pressure varies in accordance with certain conditions (outside air temperature, sunlight and wind).



    2. When there is moisture in the refrigeration system:


      I022117E03


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      During operation, pressure on low pressure side cycles between normal and vacuum
      		Moisture in refrigeration system freezes at expansion valve orifice, causing temporary interruption of cycle
      However, when melted, returns to normal condition
      1. Receiver dryer oversaturated
      2. Moisture in refrigeration system freezes at expansion valve orifice and blocks refrigerant circulation
      1. Replace receiver dryer
      2. Remove moisture from cycle by repeatedly evacuating air
      3. Charge appropriate volume of new refrigerant



    3. When cooling is insufficient:


      I022118E02


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure low on both low and high pressure sides
      2. Bubbles are seen through sight glass continuously
      3. Cooling performance insufficient
      		Gas leakage from refrigeration system
      1. Insufficient refrigerant
      2. Refrigerant leakage
      1. Check for gas leakage using halogen leak detector, and repair if necessary
      2. Charge appropriate volume of new refrigerant
      3. If indicated pressure value close to 0 when connected to gauge, create vacuum after inspecting and repairing location of leakage



    4. When the circulation of the refrigerant is poor:


      I022119E02


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure low on both low and high pressure sides
      2. Frost exists on piping from condenser to A/C unit
      		Refrigerant flow obstructed by dirt in condenser
      		Condenser clogged
      		Replace condenser



    5. When the refrigerant does not circulate:


      I022120E15


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Vacuum indicated on low pressure side, and extremely low pressure indicated on high pressure side
      2. Frost or condensation seen on piping on both sides of condenser or expansion valve
      1. Refrigerant flow obstructed by moisture or dirt in refrigeration system
      2. Refrigerant flow obstructed by gas leakage from expansion valve
      		Refrigerant does not circulate
      1. Check expansion valve
      2. Clean expansion valve with compressed air
      3. Replace condenser
      4. Evacuate air and then charge appropriate volume of new refrigerant
      5. For gas leakage from expansion valve, replace expansion valve



    6. When the refrigerant is overcharged or cooling of condenser is insufficient:


      I022121E03


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure extremely high on both sides
      2. No air bubbles are seen through sight glass even when engine rpm lowers
      1. Excessive refrigerant
      2. Cooling performance of condenser insufficient
      1. Excessive refrigerant
      2. Cooling performance of condenser insufficient
      1. Clean condenser fins
      2. Check condenser fan motor operation by switching A/C ON
      3. If 1 and 2 normal, check amount of refrigerant and charge appropriate volume of refrigerant



    7. When there is air in the refrigeration system:


      I022122E02


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure extremely high on both low and high pressure sides
      2. Low pressure piping too hot to touch
      3. Bubbles can be seen through sight glass
      		Air in refrigeration system
      1. Air in refrigeration system
      2. Insufficient vacuum purging
      1. Check whether compressor oil dirty or insufficient
      2. Evacuate air and charge new refrigerant



    8. When the expansion valve malfunctions:


      I022123E02


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure extremely high on both low and high pressure sides
      2. Frost or condensation on piping on low pressure side
      		Expansion valve malfunction
      1. Excessive refrigerant in low pressure piping
      2. Expansion valve opening too wide
      		Replace expansion valve



    9. When the compressor is defective:


      I022124E02


      Symptom
      		Probable Cause
      		Diagnosis
      		Corrective Action
      1. Pressure extremely high on both low and high pressure sides
      2. Pressure extremely low on high pressure side
      		Internal leakage in compressor
      1. Compression failure of compressor
      2. Leakage from damaged valve or broken sliding parts in compressor
      		Repair or replace compressor



3. INSPECT IDLING SPEED

  1. Warm up the engine.

  1. Inspect idling speed when these conditions are established.

    Standard:
    for 1KR-FE CVT 
    Condition
    		Idling Speed
    Switch A/C off
    		700 rpm
    Switch A/C on
    		780 rpm

    Standard:
    for 1KR-FE Manual Transaxle 
    Condition
    		Idling Speed
    Switch A/C off
    		780 rpm
    Switch A/C on
    		800 rpm

    Standard:
    for 1NR-FE CVT 
    Condition
    		Idling Speed
    Switch A/C off
    		650 rpm
    Switch A/C on(Lo)
    		700 rpm
    Switch A/C on(Hi)
    		850 rpm

    Standard:
    for 1NR-FE Manual Transaxle 
    Condition
    		Idling Speed
    Switch A/C off
    		600 rpm
    Switch A/C on(Lo)
    		700 rpm
    Switch A/C on(Hi)
    		850 rpm

    Standard:
    for 1ND-TV 
    Condition
    		Idling Speed
    Switch A/C off
    		720 to 830 rpm
    Switch A/C on
    		850 rpm
    Switch PWR HEAT on
    		950 rpm