A/C Refrigerant System Contamination:TXV Replacement (24-16-92)

A/C REFRIGERANT SYSTEM CONTAMINATION:TXV REPLACEMENT

TECHNICAL SERVICE BULLETIN

A/C REFRIGERANT SYSTEM CONTAMINATION

Model(s): 1993 (LH) Concorde/intrepid/Vision

Group: Air Conditioning

Bulletin No.: 24-16-92

Date: December 14, 1992

SYMPTOM/CONDITION

Some vehicle A/C systems may work well for a few days, then suddenly stop producing cool air. If the A/C compressor runs continuously and the condition exists in the fresh-air and recirculation mode, the thermostatic expansion valve (TXV) may be blocked by contamination from loose filter drier desiccant. This condition affects vehicles built before August 20, 1992, (MDH 08-20-XX)

DIAGNOSIS

1. Recalibrate HVAC unit via the A/C control panel.
2. Re-evaluate A/C system for proper vehicle air cooling.

   - If system is functioning properly, discontinue diagnosis.

   - Otherwise, continue with next step.

3. Run A/C system in full cold, fresh air mode (panel setting recommended) with gages set up to read compressor suction and discharge pressure, and a DRB II (Scan Tool) set up to read the evaporator temperature.

   - If the suction pressure gage reads 10 psi or less and the discharge pressure is between 100 and 150 psi, then the expansion valve is probably blocked with contaminant.

   - This is confirmed if the evaporator temperature is remaining near the ambient temperature.

   - If both conditions are met, perform the repair procedure.

4. If the system pressures and evaporator temperature do not match the conditions of the previous step, test the A/C system for other problems that could lead to the malfunction, i.e., low refrigerant charge level, condenser fan malfunctions, etc.

Qty.	Description	Part Number
1	Filter Drier Bottle and Bracket Assembly	4592056
1	Liquid Line Assembly	4596031
1	Expansion Valve Assembly	4596077

REPAIR PROCEDURE

1. Replace the thermostatic expansion valve, A/C liquid line, and filter drier bottle.
2. Verify A/C operation.