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Q: The heater is hot as long as you keep the blower on low, but gets cold when you turn it up

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My heater works good with the heat on low but once I turn it up turn the blower up on it gets cold

My car has 187000 miles.
My car has an automatic transmission.

A: Hi there. The issue you’re describing is ty...

Hi there. The issue you’re describing is typically caused by a heater blower motor resister that is malfunctioning or the heater core that might be obstructed with debris. In both cases, removing the dashboard to inspect and diagnose the precise source of your heating system issue will need to be completed. There are other possible components that may be faulty including a heater control valve or temperature sensor that can be checked out during an inspection of the heating system.

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