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Q: AC blows hot air - 2005 Mercedes-Benz SLK350

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I've been having some issues with the AC system in my car. The AC would start blowing hot air. This happened several times already. It would start working correctly when I restart the car after a while. Yesterday this occurred again so I restarted the car but the AC wasn't working properly. What is causing this?

Several heater/AC components could cause this problem. A bad interior temperature sensor, a bad heater/AC control module, or a bad heater control valve (electrically controlled) may be allowing the hot water valve to stay open, circulating hot water when it’s not appropriate. A YourMechanic professional can help diagnose your vehicles malfunctioning air conditioning and make necessary repairs.

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