The accumulator functions as a liquid/vapor separator. The accumulator receives the following refrigerant products from the evaporator:

The accumulator only allows refrigerant vapor and oil to continue on to the compressor. The accumulator is located on the passenger side of the engine compartment, between the air cleaner assembly and the blower case.

Desiccant is located at the bottom of the accumulator. Desiccant acts as a drying agent for moisture that may have entered the system. An oil bleed hole is also located near the bottom of the accumulator outlet pipe in order to provide an oil return path to the compressor.

Do not repair the accumulator. Replace the accumulator if diagnosis leads to a failed accumulator.

The compressor is belt-driven from the engine crankshaft through the compressor clutch pulley. The compressor pulley rotates freely, without turning the compressor shaft, until an electromagnetic clutch coil is energized. When voltage is applied in order to energize the clutch coil, a clutch plate and hub assembly is drawn toward the pulley. The magnetic force locks the clutch plate and pulley together as one unit in order to drive the compressor shaft. The air conditioning compressor is located on the passenger side of the vehicle. The air conditioning compressor bolts to the front of the engine.

The Headered-Tube and Center (HTC) type condenser is made of cross tubes. Cross tubes carry the refrigerant and cooling fins. Refrigerant and cooling fins provide rapid transfer of heat. Air passing through the condenser cools the high-pressure refrigerant vapor causing the vapor to condense into a liquid. The condenser is located in front of the radiator.

The plastic expansion tube contains a fixed-diameter tube with a mesh filter screen at either end. The expansion tube is located in the evaporator inlet pipe. The tube creates a restriction to the high-pressure liquid refrigerant in the liquid line. This restriction meters the flow of refrigerant to the evaporator as a low-pressure liquid. When the engine is turned OFF with the air conditioning operating, the refrigerant in the system will flow from the high-pressure side of the expansion tube to the low-pressure side of the tube. This flow continues until the pressure is equalized. This may be detected as a faint sound of liquid flowing (hissing) for 30 to 60 seconds. The hissing is a normal condition.

When system diagnostics indicate a restricted expansion tube, replacing the expansion tube may not be necessary. Use compressed air in order to remove any of the following debris from the screen:

The expansion tube may be reused if the following conditions exist:

The expansion tube is located inside the suction line at the condenser.

The evaporator cools and dehumidifies the air before the air enters the vehicle. High pressure liquid refrigerant flows through the orifice tube into the low pressure areas of the evaporator. The heat in the air passing through the evaporator core is lost to the cooler surface of the core, thereby cooling the air. The following conditions occur during heat loss from the air to the evaporator core surface:

The evaporator is located inside the blower case. The blower case is located on the passenger side of the engine compartment.

In any air conditioning mode, the heater core heats the cool, dehumidified air in order to achieve the desired air temperature. The position of the control assembly temperature knob determines how much heat is added to the incoming air. The heater core is located inside the heater case, on the passenger side of the cowl.

The compressor is equipped with a pressure relief valve as a safety factor. Under certain conditions, the refrigerant on the discharge side may exceed the designed operating pressure. Exceeding this pressure limit may cause refrigerant loss. In order to prevent refrigerant loss or system damage, the valve opens automatically at approximately 3 036 kPa (440 psi). When the valve opens, current to the compressor clutch is interrupted. Correct any condition that causes the valve to open. The high pressure relief valve is located on the air conditioning compressor.

Caution: Avoid breathing the A/C Refrigerant 134a (R-134a) and the lubricant vapor or the mist. Exposure may irritate the eyes, nose, and throat. Work in a well ventilated area. In order to remove R-134a from the A/C system, use service equipment that is certified to meet the requirements of SAE J 2210 (R-134a recycling equipment). If an accidental system discharge occurs, ventilate the work area before continuing service. Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.

Like the coolant in the engine cooling system, the refrigerant performs the following operations in the air conditioning system:

Although various substances are used as refrigerants in other types of refrigeration systems, some automotive air conditioning systems use Refrigerant-12 (R-12).

This vehicle uses Refrigerant-134a (R-134a). R-134a has the following properties:

Notice: R-134a refrigerant is not compatible with R-12 refrigerant in an air conditioning system. R-12 in a R-134a system will cause compressor failure, refrigerant oil sludge, or poor air conditioning system performance.

While the R-134a A/C system is very similar to an R-12 A/C system, the differences in the following items are important: