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Q: AC works well briefly, then blows warm

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Hi, I need some advice on what to do with the air conditioning that works well only briefly. Then the light begin to flash and it starts malfunctioning and only warm air comes out. If I restart it, it would work well again but only shortly. I filled it with the refrigerant coolant but it didn't solve the problem. I had the relay checked and it's good. What should I do? Thanks.

Hello there. A few different things can cause the AC to shut off after a short while. The first being an overfilled AC refrigerant. When this occurs, the pressure in the system rises too high and causes the AC to shut off. Another possible cause is the AC high pressure switch itself failing. When this happens the car will shut off the AC thinking that the pressure is too high. A qualified technician like one from YourMechanic will be able to diagnose your AC problem and perform any repairs that may be required.

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