why does honda civic ac screech when at a stop
It works fine when on the road, but when I stop at a light it starts screeching and I have to turn the ac off.
leave it off, unplug compressor, see a specialist or your dealer. Some issue is causing pump failure. You need qualified, schooled, experienced help. Systems of several origins can be in a car, identifying what who where is first step.
Check the A/C fan out in front, it should turn on the instant you start the A/C, if it doesn't then the fluid pressures are getting too high causing the compressor to pressure lock and the belt to squeal.
The relays for cooling fans can get damaged by a battery that slides around on those cars.
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