Skip the auto shop - Our mechanics make house calls

Q: AC Blowing from vents and defrost

asked by on

When I have the control knob for AC on front vents it blows out of all the vents including defrost. If I have the knob set to defrost the air only comes out of the defrost vents. What could be causing this issue?

My car has 70150 miles.
My car has an automatic transmission.

A: The air conditioner blend door is controlle...

The air conditioner blend door is controlled by an electronic actuator and if the door is not in set position then you may have a defective actuator and need to replace it. The door operation should be in the manual mode to make sure the actuator is defective or there is a blend door stuck from something getting down in vent door. Sometimes a pen, paper clip, or pencil can fall in the defroster vent and can lodge in the door and not let it seal. If this is the case, then the evaporator case may need removed to get out the item out of the case door. I would have a professional scope out your AC system firsthand and determine what fixes will help.

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: Car overheating and not defrosting properly.

Hi, I have seen this issue quite often on the PT Cruiser. This is typically caused by a failure in the heater core that is located in the dash. This part carries hot coolant into the interior of the car...

Q: will the radiator and clutch from a 00 coupe fit my 03

Unfortunately, without knowing the specific model of your Hyundai and the motor it came with, there is no way to tell if the radiator and clutch may be interchangeable.

Q: How do you get maximum cooling with the Dual Zone Automatic Climate Control?

During very hot weather, you may find that normal air conditioning operation doesn’t quite cut it. There are two ways that you can obtain maximum cooling with your car. Here’s what you should know: Auto: You can use the...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...