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

asked by on September 10, 2016

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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