INSPECTION
| Symptom | Probable cause | Repair order |
|---|---|---|
| High-pressure side is unusually high. | Defective condenser fan motor Clogged condenser fin Too much refrigerant Air inside the system Defective receiver dryer | Replace the fan motor. Clean the condenser fin. Discharge refrigerant. Replace the receiver dryer. After re-evacuating the receiver dryer, charge appropriate amount of refrigerant. |
| High-pressure side is unusually low. | Defective compressor Not enough refrigerant Clogged expansion valve Expansion valve frozen temporarily by moisture | Replace the compressor. Check for leaks. Replace the expansion valve. Fully evacuate the expansion valve. |
| Low-pressure side is unusually high. | Defective compressor Defective expansion valve Too much refrigerant | Replace the compressor. Replace the expansion valve. Discharge refrigerant. |
| Low-pressure side is unusually low. | Not enough refrigerant Clogged expansion valve Expansion valve frozen temporarily by moisture Saturated receiver dryer | Check for leaks. Replace the expansion valve. Replace the receiver dryer. |
REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET DIAGNOSIS
Operate the A/C system for approx. 10 minutes, and confirm that the high-pressure side shows at least 690 kPa (7.03 kg/cm 2 , 100 psi). Then stop the engine to start the leak test.
Starting from the connection between the high-pressure pipe and evaporator, check the system for leaks along the high-pressure side through the compressor. The following items must be checked thoroughly.
Check the joint and seam between the pressure switch (dual pressure switch) and high-pressure pipe.
Check the connections between the condenser and pipes, and welded joints on the condenser.
The leak tester may detect the oil on the condenser fins as a leak.
Check the joint between the compressor and hoses.
Check the machined area of compressor and other joints on the compressor.
Check the compressor shaft seal at the area near the center of compressor clutch pulley.
Some shaft seals show a slight amount of leakage about 3 g (0.1 oz) per year. This is not a problem.
Starting from the connection between the low-pressure pipe and evaporator, check the system for leakage along the low-pressure side through the compressor. The following items must be checked thoroughly.
Scheme 2
- Connection between two parts
- Connection between the pipe and plate
Visually check the rubber area of the flexible hose for cracks.
Check the entire length of the flexible hose, especially the connection with the metal hose end.
| IMPORTANT | Carefully check the external surface of hoses and tubes at approx. 25 mm (0.98 in) per second. |
Scheme 3
- Flexible hose
Disconnect the drain hose from the heater case, and check the hose end for at least 10 seconds.
After the test is finished, reconnect the drain hose.
Turn the ignition key to ON position, and run the blower at high speed for 1 minute. Stop the blower to check the ventilation grille on the instrument panel. While moving the tester closer to the grille, run the blower for 1 or 2 seconds, then stop it. Check the grille at that point for at least 10 seconds.
Scheme 4
Check the valve in the service port.
Visually check the rubber seal in service port cap.
Scheme 5
Connect the motor connector terminal 1 from the battery to the positive (+) lead and terminal 2 to the negative (- ) lead. Make sure the motor runs smoothly.
Scheme 6
Confirm that no dust or insects are found on the condenser fins. Air-blow or flush fins with water as needed.
Confirm that no oil leaks from condenser. If a failure is found, replace the condenser with a new one.
Note. If cracking, damage, or swelling is found on a hose, replace it with a new one.
Scheme 7
(3) - (4): Continuity exists.
(1) - (2): No continuity
While applying battery voltage to the terminal between (3) and (4), check continuity between (1) and (2).
If no continuity exists, replace the relay with a new one.
Scheme 8
- Joint box
- Main fuse box
| Main Fan Relay 1 | A |
|---|---|
| Main Fan Relay 2 | B |
| Sub Fan Relay 1 | C |
| Sub Fan Relay 2 | E |
| A/C Relay | D |
| Main Fan Fuse | F |
| Sub Fan Fuse | G |
| A/C Fuse | H |
RELAY AND FUSE REFERENCE
Connect the manifold gauge to the service valve on high-pressure side.
Remove the pressure switch harness connector. Using a circuit tester, inspect the ON-OFF operation of pressure switch.
Scheme 9
| Terminal No. | Operation | Standard kPa (kg/cm 2 , psi) | |
|---|---|---|---|
| High and low pressure switch | 1 and 2 | Turns OFF. | Increasing to 2,800+/-100 (29+/-1, 406+/-15) |
| Decreasing to 278+/-29 (2.83+/-0.3, 40.3+/-4.2) | |||
| Turns ON. | Increasing to 287+39/- 25 (2.9 +0.4/- 0.25 42+5.7/ - 3.6) | ||
| Decreasing to 2,200+/-200 (22.4+/-2, 319+/-29) |
PRESSURE SWITCH ON-OFF OPERATION REFERENCE
The direction and amount of air should be adjusted smoothly.
The adjustment should be kept in each position.
| Symptom | Repair order | |
|---|---|---|
| Blower motor | Doesn't move. | Fuse |
| Blower motor relay | ||
| Blower motor | ||
| Blower motor resistor | ||
| Blower switch | ||
| Wire harness | ||
| Strange noise. | Blower motor | |
| Compressor | Doesn't move. | Refrigerant |
| Fuse | ||
| Air conditioning relay | ||
| Magnet clutch | ||
| Compressor | ||
| Pressure switch | ||
| A/C switch | ||
| Blower switch | ||
| Wire harness | ||
| Noise | V-Belt | |
| Magnet clutch | ||
| Compressor | ||
| Cold air not emitted. | Refrigerant | |
| V-Belt | ||
| Magnet clutch | ||
| Compressor | ||
| Pressure switch | ||
| A/C switch | ||
| Blower switch | ||
| Wire harness | ||
| Heater duct | ||
| Heater vent duct | ||
| Warm air not emitted. | Engine coolant | |
| Blower switch | ||
| Heater core | ||
| Temperature of air from vents does not change. | Engine coolant | |
| Air mix actuator (Auto A/C) | ||
| Wire harness (Auto A/C) | ||
| Temperature cable (Manual A/C) | ||
| Unable to switch blow vents. | Mode actuator (Auto A/C) | |
| Air flow switch (Auto A/C) | ||
| Wire harness (Auto A/C) | ||
| Mode cable (Manual A/C) | ||
| Unable to switch suction vents. | Air inlet select switch (Auto A/C) | |
| FRESH/RECIRC actuator (Auto A/C) | ||
| Wire harness (Auto A/C) | ||
| Intake cable (Manual A/C) | ||
SYMPTOM AND REPAIR ORDER REFERENCE