Questions and Answers

Dodge Intrepid A/C Problems Q. Dear Vincent: 1993 Dodge Intrepid 3.3 liter V-6 Automatic transmission 109,000 miles Fuel Injection P/S, A/C, Cruise control Rack & Pinion steering

With the A/C switch pushed on, the air blowing is not cold. Visually checked compressor and condenser for debris, cracks, and leaks, none found. I pulled out A/C relay and checked it for continuity, and then supplied 12 volts to relay and listened for gate to "click".

So far so good. With the relay still removed, I ran a jumper to complete the circuit in the relays spot and listened for the magnetic clutch on the compressor to engage, which it did. Finally, with the motor running I pushed the A/C switch and turned on the blower.

With the A/C relay still removed, I tried to assess the amount of current that was flowing to the A/C relay as someone was in the car pushing the A/C button on and off. The voltmeter did not register any readings. Can you help me? My mother would sure appreciate it.

Mark

A. The A/C system has a pressure sensing switch in the lines which precludes the compressor clutch from engaging when the system is discharged. When the pressure switch breaks the circuit it prevents voltage from passing to the relay.

Discharges occur due to either slow or fast leaks, through the various fittings and the rotary seal in the compressor. You can pick up an inexpensive A/C pressure check gauge at most auto parts stores to determine if the system is discharged. The gauge looks similar to a tire pressure gauge and is simply pressed onto the Schrader valves after the protective caps are removed.

You can also purchase an R-134A retrofit kit with leak detector dye if you want to continue to troubleshoot and repair the A/C yourself. If you want to restore the original R-12 Freon, you will have to take the car to a licensed A/C technician for further service.