Toyota Corolla Cross: On-vehicle Inspection

ON-VEHICLE INSPECTION

CAUTION / NOTICE / HINT

HINT:

• Steps 2 to 9 specify the procedure to determine the cause of a refrigerant leak.
• Step 10 specifies the procedure to check if there is a clog in the expansion valve.

PROCEDURE

1. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

HINT:

The following examples show the readings of a manifold gauge set and the corresponding air conditioning system problems.

(a) Read the manifold gauge pressure when the following conditions are met:

• Doors are fully open.
• The engine is idling.
• The A/C switch is on.
• The temperature is set to max cool.
• The blower speed is set to high.
• Temperature at the air inlet with recirculate selected is 30 to 35°C (86 to 95°F).

(1) Normally functioning air conditioning system Gauge Reading Pressure Side Refrigerant Volume Low 150 to 250 kPa (1.5 to 2.5 kgf/cm2, 22 to 36 psi) High 1370 to 1570 kPa (14.0 to 16.0 kgf/cm2, 199 to 228 psi)

(2) Abnormally functioning air conditioning system

1. During operation, pressure on low pressure side cycles between normal and vacuum

   *a	LO
   *b	HI

   Symptom	Air conditioning system periodically cools and then fails to cool
   Probable Cause	Moisture in air conditioning system freezes at expansion valve orifice, causing refrigerant to temporarily stop circulating
   	After system stops and warms up again, ice melts and normal operation is temporarily restored
   Diagnosis	Cooler dryer (integrated into condenser tank) saturated with moisture
   	Moisture in air conditioning system is freezing at expansion valve orifice and blocking circulation of refrigerant
   Corrective Actions	Replace cooler dryer
   	Remove moisture by repeatedly evacuating air from air conditioning system
   	Recharge air conditioning system with proper amount of new or purified refrigerant

   HINT:

   For the example above, moisture is present in the air conditioning system.

2. Pressure is low on both low and high pressure sides

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively
   	Insufficient cooling performance
   Probable Cause	Refrigerant leaks from air conditioning system
   Diagnosis	Insufficient refrigerant
   	Refrigerant leaking
   Corrective Actions	Check for refrigerant leaks and repair if necessary
   	Recharge air conditioning system with proper amount of new or purified refrigerant
   	If gauges indicate pressure of close to 0, then it is necessary to evacuate air conditioning system after repairing leaks

   HINT:

   For the example above, there is insufficient refrigerant.

3. Pressure is low on both low and high pressure sides

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively
   	Frost exists on pipe from condenser to evaporator unit
   Probable Cause	Refrigerant flow is obstructed by dirt inside pipes of condenser core
   Diagnosis	Condenser is clogged
   Corrective Actions	Replace condenser

   HINT:

   For the example above, there is poor circulation of refrigerant.

4. Vacuum is indicated on low pressure side and very low pressure is indicated on high pressure side

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively (system may cool occasionally)
   	Frost or condensation is seen on piping on both sides of receiver/dryer or expansion valve
   Probable Cause	Refrigerant flow is obstructed by moisture or dirt in air conditioning system
   	Expansion valve is stuck closed
   Diagnosis	Refrigerant does not circulate
   Corrective Actions	Replace expansion valve
   	Replace condenser
   	Evacuate air conditioning system and recharge with proper amount of new or purified refrigerant

   HINT:

   For the example above, the refrigerant does not circulate.

5. Pressure is too high on both low and high pressure sides

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively
   Probable Cause	Unable to provide sufficient performance due to excessive amount of refrigerant
   	Cooling effectiveness of condenser is insufficient
   Diagnosis	Excessive amount of refrigerant in air conditioning system because excessive refrigerant was added during recharging
   	Cooling effectiveness of condenser is insufficient because condenser fins are clogged or cooling fan is faulty
   Corrective Actions	Clean condenser
   	Check operation of condenser cooling fan
   	If condenser is clean and fan operation is normal, check amount of refrigerant and recharge air conditioning system with proper amount of new or purified refrigerant

   HINT:

   For the example above, the air conditioning system is overcharged or cooling effectiveness of condenser is insufficient.

6. Pressure is too high on both low and high pressure sides

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool
   	The low pressure piping is too hot to touch
   Probable Cause	Air in air conditioning system
   Diagnosis	Air present in air conditioning system
   	Insufficient vacuum purging when evacuating air conditioning system
   Corrective Actions	Replace cooler dryer
   	Check compressor oil to see if it is dirty or insufficient
   	Evacuate air conditioning system and recharge it with new or purified refrigerant

   NOTICE:

   These gauge indications occur when the air conditioning system has been left open and then recharged without evacuating the system.

   HINT:

   For the example above, air is present in the air conditioning system.

7. Pressure is too high on both low and high pressure sides

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively
   	Frost or large amount of condensation on piping on low pressure side
   Probable Cause	Expansion valve may be stuck open or metering refrigerant incorrectly
   Diagnosis	Excessive refrigerant in low pressure piping
   	Expansion valve open too wide
   Corrective Actions	Replace expansion valve

   HINT:

   For the example above, there is an expansion valve malfunction.

8. Pressure is too high on both low and high pressure sides or pressure is too low on high pressure side

   *a	LO
   *b	HI

   Symptom	Air conditioning system does not cool effectively
   Probable Cause	Internal leak in compressor
   Diagnosis	Low compression
   	Leak from damaged valve or other compressor component
   Corrective Actions	Replace compressor

   HINT:

   For the example above, there is insufficient compressor compression.

(3) Gauge readings (Reference)

2. INSPECT LEAK INSPECTION PROCEDURE

HINT:

The following inspection specifies how to determine the cause of a refrigerant leak after determining the location of the leak using a gas leak detector. Use this procedure to determine where to clean and what to be replaced. Illustrations, specifications and part names are for reference only and may differ from the actual vehicle.

(a) Use a gas leak detector to inspect for refrigerant gas leaks.

• When leaking occurs around "A" parts in the illustration:

  Click here

• When leaking occurs around "B" parts in the illustration:

  Click here

• When leaking occurs around "C" parts in the illustration:

  Click here

• When leaking occurs around "D" parts in the illustration:

  Click here

3. INSPECT EXPANSION VALVE AND PIPE FITTING AREA

NOTICE:

• Do not reuse the O-rings once they are removed.
• Make sure to complete the steps from a to h and replace all the parts in which defects are found.
• If all the related parts are normal, foreign material may be temporarily adhering to the O-ring or there may be an airtight malfunction due to deformation.

(a) REMOVE PIPE: NOTICE: Wipe off the joint area with clean cloth before disassembly. Slowly remove a pipe straight to prevent the sealing face from being damaged and foreign materials from dropping off. (1) Remove the pipe from the expansion valve.

*1 Expansion Valve *a Pipes

(b) CHECK O-RING SURFACE IN PIPE: NOTICE: Check the O-ring surface in a well-lit place. When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire O-ring surface and make sure that it is free from defects, such as damage (cuts, dents or crushed areas), foreign material adhesion or twists. If there is any defect, clean or replace the part. Click here

*1 O-ring

(c) CHECK SEALING FACE OF PIPE: NOTICE: When removing the O-ring, use soft tools (such as tooth picks) to avoid damaging the sealing face or O-ring. (1) Remove the O-ring. (2) Check the entire pipe surface and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

(d) CHECK SEALING FACE OF EXPANSION VALVE (PIPE SIDE): NOTICE: When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire sealing face of expansion valve (pipe side) and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

(e) REMOVE EXPANSION VALVE: NOTICE: Wipe off the joint area with clean cloth before disassembly. Slowly remove a pipe straight to prevent the sealing face from being damaged and foreign materials from dropping off. When it is hard to remove, slowly sway up-and-down and right-to-left for removal. (1) Remove the expansion valve from the evaporator. HINT: If necessary, remove the air conditioning unit. Click here

*1 Evaporator *2 Expansion Valve

(f) CHECK SEALING FACE OF EXPANSION VALVE (EVAPORATOR SIDE): NOTICE: When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire sealing face of expansion valve (evaporator side) and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

(g) CHECK O-RING SURFACE IN EVAPORATOR: NOTICE: Check the O-ring surface in a well-lit place. When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire O-ring surface and make sure that it is free from defects, such as damage (cuts, dents or crushed areas), foreign material adhesion or twists. If there is any defect, clean or replace the part. Click here

*1 O-ring

(h) CHECK SEALING FACE OF EVAPORATOR: NOTICE: When removing the O-ring, use soft tools (such as tooth picks) to avoid damaging the sealing face or O-ring. (1) Remove the O-ring. (2) Check the entire evaporator surface and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

4. INSPECT CONDENSER AND PIPE FITTING AREA

NOTICE:

• Do not reuse the O-rings once they are removed.
• Make sure to complete the steps from a to d and replace all the parts in which defects are found.
• If all the related parts are normal, foreign material may be temporarily adhering to the O-ring or there may be an airtight malfunction due to deformation.

(a) REMOVE PIPE: NOTICE: Wipe off the joint area with clean cloth before disassembly. Slowly remove a pipe straight to prevent the sealing face from being damaged and foreign materials from dropping off. (1) Remove the pipes from the condenser.

*a Discharge Side *b Liquid Side

(b) CHECK O-RING SURFACE IN PIPE: NOTICE: Check the O-ring surface in a well-lit place. When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire O-ring surface and make sure that it is free from defects, such as damage (cuts, dents or crushed areas), foreign material adhesion or twists. If there is any defect, clean or replace the part. Click here

*1 O-ring

(c) CHECK SEALING FACE OF PIPE: NOTICE: When removing the O-ring, use soft tools (such as tooth picks) to avoid damaging the sealing face or O-ring. (1) Remove the O-ring. (2) Check the entire pipe surface and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Seal Surface

(d) CHECK SEALING FACE OF CONDENSER: NOTICE: When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire sealing face of condenser and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Seal Surface

5. INSPECT COMPRESSOR AND PIPE FITTING AREA

NOTICE:

• Do not reuse the O-rings once they are removed.
• Make sure to complete the steps from a to d and replace all the parts in which defects are found.
• If all the related parts are normal, foreign material may be temporarily adhering to the O-ring or there may be an airtight malfunction due to deformation.

(a) REMOVE PIPE: NOTICE: Wipe off the joint area with clean cloth before disassembly. Slowly remove a pipe straight to prevent the sealing face from being damaged and foreign materials from dropping off. (1) Remove the pipes from the compressor.

*a Discharge Side *b Suction Side

(b) CHECK O-RING SURFACE IN PIPE: NOTICE: Check the O-ring surface in a well-lit place. When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire O-ring surface and make sure that it is free from defects, such as damage (cuts, dents or crushed areas), foreign material adhesion or twists. If there is any defect, clean or replace the part. Click here

*1 O-ring

(c) CHECK SEALING FACE OF PIPE: NOTICE: When removing the O-ring, use soft tools (such as tooth picks) to avoid damaging the sealing face or O-ring. (1) Remove the O-ring. (2) Check the entire pipe surface and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

(d) CHECK SEALING FACE OF COMPRESSOR: NOTICE: When it is difficult to check the surface condition due to oil adhesion, degrease the surface (such as by wiping it with a clean white cloth). Make sure not to lose any foreign material that was adhering to the surface. (1) Check the entire sealing face of compressor and make sure that it is free from defects, such as foreign material adhesion, damage or corrosion. If there is any defect, clean or replace the part. Click here

*a Sealing face

6. INSPECT OTHER AREA

NOTICE:

• Do not reuse the O-rings once they are removed.
• Make sure to check all the related parts and replace all the parts in which defects are found.
• If all the related parts are normal, foreign material may be temporarily adhering to the O-ring or there may be an airtight malfunction due to deformation.
• Check the following parts. Refer to other procedures for details.

(a) CHECK OTHER PART:

NOTICE:

• Be sure there is sufficient light when checking the O-ring.
• If the condition of the surface is difficult to see, degrease it so it is easier to see. However, be careful when degreasing it so that any foreign matter that is attached to it is not misplaced.

(1) Check the O-ring surface of the pipe or part. Click here

*1 O-ring

(2) Check the sealing face of the pipe. Click here

*a Sealing face

(3) Check the sealing face of the part. Click here

*a Sealing face

7. INSPECT O-RING ABNORMALITY

(a) Check the O-ring for any abnormalities.

8. INSPECT SEALING FACE ABNORMALITY (O-RING ATTACHED AREA)

(a) Check the seal surface of the O-ring mount for any abnormalities.

9. INSPECT SEALING FACE ABNORMALITY (PART JOINTED AREA)

(a) Check the seal surface of the connector for any abnormalities.

10. INSPECT FOR FAULTY EXPANSION VALVE

(a) Recover refrigerant

(1) Connect the refrigerant recovery valve and recover the refrigerant.

NOTICE:

• Perform this procedure in accordance with the repair manual for each vehicle.
• Use the refrigerant recovery unit in accordance with the manufacturer's instruction manual.

(b) Install air conditioner service tool set

(1) Install the air conditioner service tool set to the vehicle (high pressure side). SST: 09985-20010

(2) Open all the valves of the air conditioner service tool set.

(3) Install the refrigerant recovery unit or vacuum pump to the vehicle (low pressure side).

(c) Inspect expansion valve

(1) Depending on the type of low pressure side hose of the air conditioner service tool set, prevent air from being drawn in as shown in the illustration.

(2) While maintaining the above state, check that the gauge on the low pressure side changes when the center hose is closed and opened as shown in the illustration.

Result	Judgement
The gauge indicates a negative pressure (approximately -50 kPa (-0.5 kgf/cm2, -7.3 psi)).	Expansion valve is normal.
The indicated gauge pressure does not change.	Expansion valve is abnormal.

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