Initial Inspection and Diagnostic Overview

ON-VEHICLE INSPECTION







1. INSPECT REFRIGERANT VOLUME
Observe the sight glass on the liquid tube.

Test conditions:
- Running engine at 1,500 rpm
- Blower speed control switch at "HI" position
- A/C switch ON
- Temperature control dial at "COOL" position
- Fully open the doors

2. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET
This is a method in which the trouble is located by using a manifold gauge set. Read the manifold gauge pressure when these conditions are established.

Test conditions:
- Temperature at the air inlet with the 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 on "COOL" position

HINT: It should be noted that the gauge indications may vary slightly due to ambient temperature conditions.




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 IAC valve and air intake system.

4. INSPECT FOR LEAKAGE OF REFRIGERANT
a. Perform in these conditions:
- Stop engine.
- Secure good ventilation (If the gas leak detector may not 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 has stopped, leave the cooling unit for more than 15 minutes.
- Expose the gas leak detector sensor under the drain hose.
- When bring 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.