The Car Care Clinic with the Dr John

88 Chrysler New Yorker - What controls the air conditioner

Question

What actually controls the air conditioner to cycle on and off on an 88 Chrysler New Yorker with the climate control heating and cooling system? How would you diagnose a problem with this system when the compressor is not cycling, assuming there is adequate freon and proper voltage going through the compressor and pressure switch?

Answer

You cannot assume that there is an adequate charge of refrigerant in the A/C system. Virtually every manufacturer's A/C system will shut down the A/C compressor if the system pressure drops below a specified pressure. The reason for this is to prevent damage to the A/C compressor and system, in the event there is a system leak. If a failed A/C system is allowed to continue operating, the lubricating oil will be forced out and contaminants would be allowed to enter the system at a much greater rate. The result would be catastrophic to the checking account. The first step in diagnosing an inoperative A/C system is to verify that there is adequate refrigerant in the system. From that point, diagnosis would turn to the electrical circuits that are responsible for activating the system. Diagnosis and repair of A/C systems requires specialized equipment, training and the technician handling the refrigerant must be federally licensed. Have your A/C system diagnosed, from that point you can determine if the repairs are something you can handle.

Good Luck!
Dr. John