A/C - Erratic Operation/Poor Peformance

NO.: 24-16-92
GROUP: Air Conditioning
DATE: Dec. 14, 1992

SUBJECT:
A/C Refrigerant System Contamination

MODELS:

1993 (LH) Concorde/Intrepid/Vision

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 per service manual procedure.

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.

PARTS REQUIRED:

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 as outlined in the 1993 Concorde/Intrepid/Vision Service Manual, Publication No. 81-270-3140.

2. Verify A/C operation.

POLICY:
Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:

Labor Operation No. 24-35-30-90 1.4 Hrs.

FAILURE CODE: 41 - Foreign Material