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Q: Heat and air

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The heat and AC both do not work. The blower works but no changes for either. Ac is as hot as it is outside and heat is as cold as it is outside. No matter what settings I try it doesn't change anything. Any ideas as what the problem could be? It's starting to get cold and with 3 kids this is kinda important. Another thing what would cause the thermostat gauge on the dash to not work? It never moves up or down just sits at like a 1/4th rather car is on or off. Could this be what is wrong with the heat? Could there just not be a thermostat in it?

My car has 166000 miles.
My car has an automatic transmission.

A: Hello. If the temperature is not changing a...

Hello. If the temperature is not changing at all then most of the time this is caused by an issue with the blend door motor. If this has failed then the temperature door will be stuck in one position. I usually check and make sure that the door will move freely and check the power going to the motor. If the motor is receiving power but not moving then the motor for the blend door needs to be replaced. It can also be the evaporator temperature sensor but that is not as common. If you need assistance, a certified YourMechanic technician can come to your location to perform a heating / AC inspection on your vehicle and suggest any repairs needed to fix this issue.

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