Initial Inspection and Diagnostic Overview
ON-VEHICLE INSPECTION1. REMOVE LUGGAGE COMPARTMENT TRIM BOX COVER
2. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET
a. This is a method to specify the trouble area by using a manifold gauge set. Read the manifold gauge pressure when the following conditions are fullfilled.
Test conditions:
- Engine has been warmed up.
- All doors are fully open.
- A/C switch is ON.
- Engine is at idle.
- Air inlet mode selector damper is at RECIRE.
- Temperature control dial is at "MAX. COOL".
- Blower speed control switch is at "HI".
- Air outlet damper is at FACE.
- Temperature at the air inlet is 30-35°C (86-95°F).
- Sunshine is shut off.
1. Normally functioning refrigeration system
Gauge reading
Low pressure side: 0.15 - 0.25 MPa (1.5 - 2.5 kgf/sq.cm)
High pressure side: 1.37 - 1.57 MPa (14 - 16 kgf/sq.cm)
2. Moisture present in refrigeration system.
3. Insufficient cooling
4. Poor circulation of refrigerant
5. Refrigerant does not circulate
6. Refrigerant overcharged or insufficient cooling of condenser
7. Air present in refrigeration system
8. Expansion valve improperly
9. Defective compression compressor
3. INSPECT IDLE-UP SPEED
a. Warm up engine.
b. 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
If idle speed is not as specified, check idle control system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
a. Perform in these conditions:
- Stop engine.
- Secure good ventilation (If not the gas leak detector may react to volatile gases which 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/sq.cm, 57 - 85 psi)
b. Bring the gas leak detector close to the drain hose before performing the test.
HINT:
- After the blower motor stopped, leave the cooling unit for more than 15 minutes.
- Expose the gas leak detector sensor under the drain hose.
- When bringing the gas leak detector close to the drain hose, make sure that the gas leak detector does not react to the volatile gases.
If such reaction is unavoidable, the vehicle must be lifted up.
c. If gas leak is not detected on the drain hose, remove the blower resistor from the cooling unit. Then insert the gas leak detector sensor into the unit and perform the test.
d. 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.
e. Bring the gas leak detector close to the refrigerant lines and perform the test.
5. REINSTALL LUGGAGE COMPARTMENT TRIM BOX COVER