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Why won't cars let you select the Face vents and defrost vents at the same time?
Wiki User
∙ 15y ago
The Heating/ ventilation systems in cars are large structures throughout the dash board, that have many channels of which air can flow through. When you use your face vents, the air is blowing from the upper vent channels. If you use the windshield defroster, the air comes from the very same upper channels, the channels just switch. They have a divider that blocks airflow one way or another. Very much like train tracks, when you change the settings with the switches, the airflow changes because the divider has moved. Therefore you cannot use both at once. The only reason why you can use the foot vents, and face vents at the same time, is because they have a divider that splits the channel that they share, you can use face vents (full force), foot vents (full force) or both split (half force). The Defroster is made to work fast, so if you use the face, and defroster vents at the same time, the defroster would be half as effective. This is why you cant use them both at the same time.
Wiki User
∙ 15y ago
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Why does your air only blows out the front vents and not the floor are defrost on your 2003 dodge ram?
This is the same on all cars. When the air flow is OFF in a section, the it blows stronger to the other vents. In this case the ones for the windshield. This makes defrosting quicker so you can start driving safely sooner.
Why do you not have air flow from the dash vents on a 2002 Mercury Sable when the defrost and floor vents work fine?
Your most likely issue is a bad hvac control switch. On older cars, this was operated by vacumm pressure, but on a 2002, it is all electrical. It may be that you need to replace the whole control unit.
What is the button that defrost the back glass in cars called?
rear defroster
Do cars made for Florida have defrost and heat?
Yes they have a heater/defroster.
Car heater just defrost work?
When you set the control, if you chose defrost, it usually does it at the temperature you specify. So if you want heat only blowing through the windshield vents, which I believe may be the question you are asking, it varies between makes of cars. This is what to look for : defrost, fan speed, temperature. If you mean "Can a car that only has a heater ( no air conditioning ) be used to defrost?" The answer is still yes. I believe the question is missing words. It is comparable to asking "Hand, just finger work?" You might try asking again, being more specific, explaining why it is a problem.
What are in all cars?
All cars have radios and vents for the air conditoner
Why does antifreeze leak from cars?
Initially, no you had best not select any various cars
Why does your car shake when the defrost is on?
Usually it is because most cars turn on the airconditioner as part of the defrost system. If your car has not been tuned up etc it may be too much load at idle.
When accelerating the ac air switches from the front to the defrost whats wrong?
In most cars the duct selection controller is vacuum pressure actuated. There is an apparent problem with the selector diaphragm. When you accelerate you create more vacuum pressure that overwhelms the diaphragm and hence the duct change. It may be as simple as a leaky hose in the dash. Most systems default to the defrost vents in the case of vacuum failure. To sum it up, it is a vacuum problem. Y-THINK-Y
Your heat is not blowing out of your floor vents but they blow out of the defrost and upper vents what could be wrong?
My guess is that you have a vacuum line that isn't connected or that has a hole. In the cars I've driven, the blower blows air into the heater box, where the heater core lives. Vacuum lines open and close flaps (or doors) on the heater box to direct the air where the control unit says it should go. These lines are usually rubber tubing, and the ends can dry out and crack, causing leaks. I have never worked on a dodge, but I've replaced miles of vacuum line on other cars.
How do you free run on Gran Turismo 5?
You go to GT Life and then practice, then select your car and track or you can go to arcade and select a track from there and then select a car from the chosen cars or your gt5 favourate cars.
Power steering belt squeals when defrost is on?
Tighten the belt. The belt drive the AC compressor. On some cars the compressor engages when the defrost is on to remove moisture from the air before it's heated for the defrosters.
