Heating, Ventilation, and Air Conditioning: Other Saturn Aura I

Fluorescent Leak Detector

Fluorescent dye will assist in locating any leaks in the A/C system.

1. Condensation on the evaporator core or the refrigerant lines may wash the PAG oil and fluorescent dye away from the actual leak. Condensation may also carry dye through the HVAC module drain.
2. Leaks in the A/C system will be indicated in a light green or yellow color when using the leak detection lamp. Use the leak detection lamp in the following areas: All fittings or connections that use seal washers or O-rings All of the A/C components The A/C compressor shaft seal The A/C hoses and pressure switches The HVAC module drain tube, if the evaporator core is suspected of leaking The service port sealing caps The sealing cap is the primary seal for the service ports.
3. Follow the instructions supplied with the J 42220 .
4. To prevent false diagnosis in the future, thoroughly clean the residual dye from any area where leaks were found. Use a rag and the approved J 43872 . See «Special Tools»(ref-301492-S29180992532008101700000) .

Fluorescent Dye Injection

1. Not all of the fluorescent dyes are compatible with PAG oil. Some types of dye decrease the oil viscosity or may chemically react with the oil.
2. R-134A leak detection dye requires time to work. Depending upon the leak rate, a leak may not become visible for between 15 minutes and 7 days.
3. To prevent false diagnosis, thoroughly clean any residual dye from the service port with a rag and the approved fluorescent dye cleaner J 43872 . See «Special Tools»(ref-301492-S29180992532008101700000) .

Halogen Leak Detector

Ensure that the vehicle has at least 0.45 kg (1 lb) of refrigerant in the A/C refrigeration system in order to perform a leak test. Refer to Refrigerant Recovery and Recharging for recharging the A/C system.

Clean and dry all surfaces in order to prevent a false warning. Liquids will damage the detector.

Follow the instructions supplied with the J 39400-A . See Special Tools .

Defrosting Insufficient

Eliminating Air Conditioning Odor

Odors may be emitted from the air conditioning system primarily at start up in hot, humid climates. The following conditions may cause the odor

1. Debris is present in the HVAC module.
2. Microbial growth on the evaporator core

When the blower motor fan is turned on, the microbial growth may release an unpleasant musty odor into the passenger compartment. To remove odors of this type, the microbial growth must be eliminated. Perform the following procedure

Deodorize the evaporator core using Deodorizing Aerosol Kit.

Perform the following steps in order to deodorize the A/C system

1. Ensure that the plenum which draws outside air into the HVAC module is clear of debris.
2. Disable the A/C compressor clutch operation by disconnecting the clutch coil electrical connector.
3. Dry the evaporator core by performing the following steps: Start the engine. Select the warmest temperature setting. Select the recirculation mode. Run the blower motor on high for 10 minutes.
4. Locate an area in the air conditioning duct between the blower motor and the evaporator core downstream of the blower motor.
5. Drill a 3.175 mm (0.125 in) hole where the hole will not interfere with or damage the following components: The blower motor The evaporator core Any other operating part the of system
6. Wear safety goggles and latex gloves in order to perform the following actions: Select the maximum blower speed. Insert the deodorizer extension tube into the hole to the mark on the extension tube. Use short spray bursts and vary the direction of spray for a 2-3 minute period of time.
7. Shut the engine OFF. Allow the vehicle to sit for 3-5 minutes.
8. Seal the 3.175 mm (0.125 in) hole with body sealer or RTV gasket compound.
9. Start the engine.
10. Operate the blower motor on high for 15-20 minutes to dry.
11. Reconnect the A/C compressor clutch coil electrical connector.
12. Verify proper clutch operation.

Refrigerant Recovery and Recharging

Tools Required

1. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(ref-301492-S29180992532008101700000) .
2. J 45037 A/C Oil Injector. See «Special Tools»(ref-301492-S29180992532008101700000) .

Note. R-134a is the only approved refrigerant for use in this vehicle. The use of any other refrigerant may result in poor system performance or component failure.

Note. To avoid system damage use only R-134a dedicated tools when servicing the A/C system.

Note. Use only Polyalkylene Glycol Synthetic Refrigerant Oil (PAG) for internal circulation through the R-134a A/C system and only 525 viscosity mineral oil on fitting threads and O-rings. If lubricants other than those specified are used, compressor failure and/or fitting seizure may result.

Note. R-12 refrigerant and R-134a refrigerant must never be mixed, even in the smallest of amounts, as they are incompatible with each other. If the refrigerants are mixed, compressor failure is likely to occur. Refer to the manufacturer instructions included with the service equipment before servicing.

The J 43600 is a complete air conditioning service center for R-134a. See Special Tools . The ACR 2000 recovers, recycles, evacuates and recharges A/C refrigerant quickly, accurately and automatically. The unit has a display screen that contains the function controls and displays prompts that will lead the technician through the recover, recycle, evacuate and recharge operations. R-134a is recovered into and charged out of an internal storage vessel. The ACR 2000 automatically replenishes this vessel from an external source tank in order to maintain a constant 5.45-6.82 kg (12-15 lbs) of A/C refrigerant.

The ACR 2000 has a built in A/C refrigerant identifier that will test for contamination, prior to recovery and will notify the technician if there are foreign gases present in the A/C system. If foreign gases are present, the ACR 2000 will not recover the refrigerant from the A/C system.

The ACR 2000 also features automatic air purge, single pass recycling and an automatic oil drain.

Refer to the J 43600 ACR 2000 manual for operation and setup instruction. See Special Tools . Always recharge the A/C System with the proper amount of R-134a. Refer to Refrigerant System Capacities for the correct amount.

A/C Refrigerant System Oil Charge Replenishing

If oil was removed from the A/C system during the recovery process or due to component replacement, the oil must be replenished. Oil can be injected into a charged system using J 45037 . See Special Tools . For the proper quantities of oil to add to the A/C refrigerant system, refer to Refrigerant System Capacities .

Balancing Procedure

1. The replacement compressor is shipped with the total system capacity of refrigerant oil.
2. Before installing the compressor, the refrigerant oil will have to be partially drained: Refer to the amount of refrigerant oil recorded during the compressor removal. Subtract the amount recorded from the total system capacity. Refer to «Refrigerant System Capacities»(ref-301492-S42102639822008101700000) . The difference between the total system capacity and the recorded amount is the calculated amount to be drained from the replacement compressor.
3. Drain the calculated amount of refrigerant oil from the replacement compressor.

Scheme 49

Scheme 50

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Scheme 52

Tools Required

1. J 37872 Universal Spanner Wrench. See «Special Tools»(ref-301492-S29180992532008101700000) .
2. J 6083 Snap Ring Pliers. See «Special Tools»(ref-301492-S29180992532008101700000) .
3. J 39400-A Halogen Leak Detector. See «Special Tools»(ref-301492-S29180992532008101700000) .

J 39400-A Halogen Leak Detector. See Special Tools .

Scheme 53

1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-301492-S16453614042008101700000) .
2. Insert 2 small screwdrivers into the 2 slots of the compressor hose and suction line connector and release locking tabs.
3. Remove the compressor hose and liquid line connector.
4. Remove the suction hose from the compressor hose.
5. Remove and discard the O-rings.
6. Remove the surge tank from the surge tank bracket.
7. Remove the suction hose and liquid line nut from the thermal expansion valve (TXV).
8. Remove the suction hose and liquid line from the TXV.
9. Remove the suction hose from the dash clip.
10. Remove the line clip from the dash.
11. Remove the refrigerant pressure sensor wire harness connector.
12. Remove the liquid line bracket bolt.
13. Remove the suction hose.
14. Remove and discard the sealing washers.

J 39400-A Halogen Leak Detector. See Special Tools .

Scheme 54

1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-301492-S16453614042008101700000) .
2. Remove the refrigerant pressure sensor wire harness connector.
3. Remove the refrigerant pressure sensor.
4. Remove the liquid line bracket bolt.
5. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-301532-S34449277472008101700000) .
6. Remove the surge tank from the surge tank bracket.
7. Remove the suction hose and liquid line nut from the thermal expansion valve (TXV).
8. Remove the suction hose and liquid line from the TXV.
9. Remove the suction hose from the dash clip.
10. Remove the liquid line from the dash clip.
11. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-301499-S33480567202008101700000) .
12. Remove the right front fender liner. Refer to «Front Fender Liner Replacement»(ref-301500-S02566820132008101700000) .
13. Remove the right radiator air deflector retainers.
14. Remove the right radiator air deflector.
15. Remove the liquid line and compressor hose bolt from the condenser.
16. Remove the liquid line and compressor hose from the condenser.
17. Remove the liquid line from the rail clip.
18. Lower the vehicle.
19. Remove the liquid line.
20. Remove and discard the sealing washers.

J 39400-A Halogen Leak Detector. See Special Tools .

Scheme 55

1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-301492-S16453614042008101700000) .
2. Remove the surge tank from the surge tank bracket.
3. Remove the suction hose and liquid line nut from the thermal expansion valve (TXV).
4. Remove the suction hose and liquid line from the TXV.
5. Remove the line clip from the dash.
6. Remove the refrigerant filter from the line.
7. Remove and discard the sealing washers.

1. J 39400-A Halogen Leak Detector. See «Special Tools»(ref-301492-S29180992532008101700000) .
2. J 46246 Valve Core Removal Tool. See «Special Tools»(ref-301492-S29180992532008101700000) .

J 39400-A Halogen Leak Detector. See Special Tools .

J 39400-A Halogen Leak Detector. See Special Tools .

J 39400-A Halogen Leak Detector. See Special Tools .

Scheme 56

Scheme 57

Scheme 58

1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-301492-S16453614042008101700000) .
2. Remove the left and right headlamp assemblies. Refer to «Headlamp Replacement»(ref-301486-S33623984482008101700000) .
3. Loop a rope around each of the 2 upper tabs of the radiator and tie the rope around the upper tie bar.
4. Remove both upper radiator support bracket bolts.
5. Remove both upper radiator support brackets.
6. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-301499-S33480567202008101700000) .
7. Remove the lower radiator air deflector retainers.
8. Remove the lower radiator air deflector.
9. Remove the right front fender liner. Refer to «Front Fender Liner Replacement»(ref-301500-S02566820132008101700000) .
10. Remove the right radiator air deflector retainers.
11. Remove the right radiator air deflector.
12. Remove the left radiator air deflector retainers.
13. Remove the left radiator air deflector.
14. Remove the liquid line and compressor hose bolt from condenser.
15. Remove the compressor hose from the condenser.
16. Remove the liquid line from the condenser.
17. Remove both lower radiator mounting bracket bolts.
18. Remove both lower radiator mounting brackets.
19. Remove and discard the condenser mounting bolts.
20. Remove and discard the condenser mounting nuts.
21. Push upward on the radiator and downward on the condenser to unsnap the condenser mounting tabs from the radiator clip.
22. Remove the condenser.
23. Remove the upper seal.
24. Remove and discard the sealing washers.

J 38185 Hose Clamp Pliers

J 38185 Hose Clamp Pliers

Engine Coolant

Engine coolant is the key element of the heating system. The engine thermostat controls the normal engine operating coolant temperature. The thermostat also creates a restriction for the cooling system that promotes a positive coolant flow and helps prevent cavitation. Coolant enters the heater core through the inlet heater hose, in a pressurized state. The heater core is located inside the HVAC module. The ambient air drawn through the HVAC module absorbs the heat of the coolant flowing through the heater core. The HVAC module distributes heated air to the passenger compartment for consistent passenger comfort. Opening or closing the HVAC module temperature door controls the amount of heat delivered to the passenger compartment. The coolant exits the heater core through the return heater hose and is recirculated back through the engine cooling system.

A/C Cycle

Refrigerant is the key element in an air conditioning system. R-134a is presently the only EPA approved refrigerant for automotive use. R-134a is an very low temperature gas that can transfer the undesirable heat and moisture from the passenger compartment to the outside air.

The A/C compressor is belt driven and operates when the magnetic clutch is engaged. The compressor builds pressure on the vapor refrigerant. Compressing the refrigerant also adds heat to the refrigerant. The refrigerant is discharged from the compressor, through the discharge hose, and forced to flow to the condenser and then through the balance of the A/C system. The A/C system is mechanically protected with the use of a high pressure relief valve. If the high pressure switch were to fail or if the refrigerant system becomes restricted and refrigerant pressure continued to rise, the high pressure relief will pop open and release refrigerant from the system.

Compressed refrigerant enters the condenser in a high temperature, high pressure vapor state. As the refrigerant flows through the condenser, the heat of the refrigerant is transferred to the ambient air passing through the condenser. Cooling the refrigerant causes the refrigerant to condense and change from a vapor to a liquid state.

The condenser is located in front of the radiator for maximum heat transfer. The condenser is made of aluminum and aluminum cooling fins, which allows rapid heat transfer for the refrigerant. The semi-cooled liquid refrigerant exits the condenser and flows through the liquid line, to the thermal expansion valve.

The thermal expansion valve is located in the liquid line between the condenser and the evaporator. The thermal expansion valve is the dividing point for the high and the low pressure sides of the A/C system. As the refrigerant passes through the thermal expansion valve, the pressure of the refrigerant is lowered. Due to the pressure differential of the liquid refrigerant, the refrigerant will begin to vaporize at the thermal expansion valve. The thermal expansion valve also meters the amount of liquid refrigerant that can flow into the evaporator.

Refrigerant exiting the thermal expansion valve flows into the evaporator core in a low pressure, liquid state. Ambient air is drawn through the HVAC module and passes through the evaporator core. Warm and moist air will cause the liquid refrigerant boil inside of the evaporator core. The boiling refrigerant absorbs heat from the ambient air and draws moisture onto the evaporator. The refrigerant exits the evaporator back through the thermal expansion valve and into the suction line and back to the compressor, in a vapor state completing the A/C cycle of heat removal. At the compressor, the refrigerant is compressed again and the cycle of heat removal is repeated.

The conditioned air is distributed through the HVAC module for passenger comfort. The heat and moisture removed from the passenger compartment will also change form, or condense, and is discharged from the HVAC module as water under the vehicle.