Skip the auto shop - Our mechanics make house calls

Q: Heat and air

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Silhouette

Many different parts can cause the vehicle to overheat. The most common would be the thermostat, radiator, water pump, air in the coolant, or a coolant leak. When a vehicle overheats at idle the usual suspect is the radiator fans....

Q: what is the easiest way to replace the upper radiator hose?

Hey there, thanks for writing in about your 1991 Mercedes-Benz 300E. You should not have to remove any engine components to replace the upper radiator hose. The only thing that you will need to do is drain the coolant. If...

Q: I recently replaced my U-Joints on my driveshaft and now my car vibrates, it gets worse the faster I'm traveling.

Hi there. Did the U-joints you installed have grease fittings and did you fill them with grease prior to driving? I know this is a basic step, but one that often gets forgotten. Dry bearings inside the u-joints wont last...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.