Air conditioner cuts out then comes back on
On a long trip my AC cuts out after driving 75 miles. I stop the car, shut off the
engine, wait a few minutes, re-start the engine, the AC works again.
The AC will often cut out if the car is running hot while driving. Does it happen more at a stop light? I would look into how the flow through the radiator is. You may get away with a cooling system flush or your rad/thermostat may need to be replaced.
Intermittent A/C Fix Just wanted to share a quick success story, in case anyone else out these is having a similar problem: Over the last couple weeks, my A/C began functioning very eratically. Most mornings on the way to work, my A/C would come on properly when I first started the car. However, after about 5-10 minutes most morning, even though the A/C switch remained lit, the A/C would cut out and produce warm air. It turned out that the compressor clutch was disengaging the A/C intermittently. Usually, it would function immediately if the car had sat unused for some time. But, whenever the A/C would flake out, I would have to turn it off and wait some time before I could get it to come on again. I eventually tracked this down to relay 384. If you open up old 384, you'll find that is contains a PC board with a large relay/solenoid and a handful of diodes, caps, and one lovely IC. When this relay switches on. it engages the A/C compressor. In my case, the pin of the relay that should go hot when the A/C is engaged was soldered to the board with a pathetically thin quantity of solder... Ah ha! Each time the A/C was engaged, the solenoid pulled the switch over to this weak contact and put pressure on it. It seems that all this daily rocking back and forth actually detached this weak solder joint. One minute of work with a soldering iron and my A/C is back!
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