On-Vehicle Inspection

WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

Inspect refrigerant volume :
Observe the sight glass on the liquid tube.

Test conditions:
- Running engine at 1,500 rpm.
- Single A/C:
  Front blower speed control dial at "HI" position.
- Dual A/C:
  Front and rear blower speed set at "HI" position.
- A/C switch ON.
- Single A/C:
  Front temperature control dial at "MAX. COOL" position.
- Dual A/C:
  Front temperature control dial at "MAX. COOL" position.
  
  Rear temperature control set at 18.5 °C (65°F).
- Fully open the doors.
Fig 1: Locating Sight Glass
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: Identifying Refrigerant Levels By Sight Glass Symptoms
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NOTE: This is a method for checking the A/C system by using a manifold gauge set. Read the manifold gauge pressure when the conditions below are met.
It should be noted that the gauge indications may vary slightly due to ambient temperature conditions.

.
Inspect refrigerant pressure with manifold gauge set :
Test conditions:
- Temperature at the air inlet with R/F switch set at RECURC is 30 - 35 °C (86 - 95 °F).
- Engine running at 1500 rpm.
- Blower speed control switch at "HI" position.
- Temperature control dial at "MAX. COOL" position.
- Dual A/C:
  Rear temperature control set at 18.5°C (65°F).
1. For normally functioning refrigeration system diagnosis, see illustrations.
  For normal gauge readings, see Fig 3-Fig 5 .
  
  Fig 3: Charting Normal Gauge Readings (Single A/C)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 4: Charting Normal Gauge Readings (Dual A/C)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 5: Displaying Normal Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. For moisture present in refrigeration system diagnosis, see illustrations. See Fig 6 and Fig 7.
  
  Fig 6: Displaying Gauge Readings with Moisture Present In System
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 7: Charting Symptoms Of Moisture In System
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. For insufficient cooling diagnosis, see illustrations. See Fig 8 and Fig 9.
  
  Fig 8: Displaying Gauge Readings For Insufficient Cooling
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 9: Charting Insufficient Cooling Symptoms
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. For poor circulation of refrigerant diagnosis, see illustrations. See Fig 10 and Fig 11.
  
  Fig 10: Displaying Gauge Readings For Poor Circulation Of Refrigerant
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 11: Charting Poor Circulation Of Refrigerant
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. For refrigerant does not circulate diagnosis, see illustrations. See Fig 12 and Fig 13.
  
  Fig 12: Displaying Refrigerant Not Circulating Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 13: Charting Refrigerant Not Circulating
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. For refrigerant overcharged or insufficient cooling of condenser diagnosis, see illustrations. See Fig 14 and Fig 15.
  
  Fig 14: Displaying Refrigerant Overcharged Or Insufficient Cooling Of Condenser Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 15: Charting Refrigerant Overcharged Or Insufficient Cooling Of Condenser
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
7. For air present in refrigeration system diagnosis, see illustrations. See Fig 16 and Fig 17.
  
  Fig 16: Displaying Air Present In Refrigeration System Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 17: Charting Air Present In Refrigeration System
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
8. For expansion valve improperly diagnosis, see illustrations. See Fig 18 and Fig 19.
  
  Fig 18: Displaying Expansion Valve Improperly Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 19: Charting Expansion Valve Improperly
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
9. For defective compression in compressor diagnosis, see illustrations. See Fig 20 and Fig 21.
  
  Fig 20: Displaying Defective Compression In Compressor Gauge Readings
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 21: Charting Defective Compression In Compressor
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Inspect idle-up speed
1. Warm up engine.
2. Inspect idle-up speed when the these conditions are established.
  - Warm up engine.
  - Blower speed control switch at "HI" position.
  - A/C switch ON.
  - Temperature control dial at "COOL" position.
  Fig 22: Charting Magnetic Clutch Engagement
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If idle speed is not as specified, check Idle control system. See Fig 22.
Inspect for leakage of refrigerant.
1. Perform in these conditions:
  - Stop engine.
  - Secure good ventilation (If not the gas leak detector may react to volatile gases witch are not refrigerant, such as evaporated gasoline and exhaust gas.)
  - Repeat the test 2 or 3 times.
  - Make sure that there is some refrigerant remaining in the refrigeration system.
    When compressor is OFF: approx. 392 - 588 kPa (4 - 6 kgf/ cm² , 57 - 85 psi)
2. Bring the gas leak detector close to the drain hose before performing the test.
3. If gas leak is not detected on the drain hose, remove the blower motor linear controller from the cooling unit. Then insert the gas leak detector sensor into the unit and perform the test.
4. Disconnect the connector and leave the pressure switch for approx. 20 minutes. Then bring the gas leak detector close to the pressure switch and perform the test.
5. Bring the gas leak detector close to the refrigerant lines and perform the test.