Common questions

Can a defrost fan blow to the floor?

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Can a defrost fan blow to the floor?

Fan Only Blows Defrost, Won’t Change To Floor Or Vent. I discovered today that I only receive air through the defrost vents. tried to change it to the floor or the dash vents, no deal.

What kind of HVAC does a 2002 S10 have?

2002 S10 HVAC stuck in vent mode. 2002 S10 ZR2 pickup. 4.3 4WD. 123,000 miles. Manual HVAC controls. No CEL and no driveability issues.

Is there any heat to feet or defrost?

No heat to feet or defrost. Before replacing Heater Control Unit, it would only blow hot air from front vents- With this replacement it will now change from cold to hot and the air flow pressure does change from the front vents when changing the setting dial but there is still no air at all to feet and defrost.

Where is the defroster located in an air conditioner?

The defroster is part of the heater and air conditioner system which is housed inside of the heater plenum. The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor.

What causes air vents to stay in defrost position?

If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.

Why is air not blowing through the vents?

The air conditioner is blowing cold and hot at the same time, cold on every vent besides the passengrer side. The air is cold so I know it is not the freon helpful? There is a blend door in your heater and it’s either stuck or not working. It ‘s electrical or vacuum.

Is the Astro fan only blows defrost?

Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. Yea the problem with them astro’s is the way the damn motor is crammed into the dog house with the heat it destroys the hard plastic vacume line . I have had 5 of them and every one had this problem until you change them out with rubber lines .

Fan Only Blows Defrost, Won’t Change To Floor Or Vent. I discovered today that I only receive air through the defrost vents. tried to change it to the floor or the dash vents, no deal.

Why does my air vent not blow to the floor?

You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position. The two doors that governs flow between dash vents and defrost/floor are “mode door 1” and “mode door 2.”

What to do when air blows out of defroster vents?

Assuming that your actuator has failed in the most common position, blowing out of the defroster vents only, you should not have to do anything other than installing the actuator motor. No indexing of the door shafts to the cam/cog or recalibration of the actuator motors.

Is there no air from the dash vents?

I have a 1999 superduty f250 early diesel, the air only blows from the floor and defrost but not the dash vents. I have swapped over known good parts from my other diesel, I have changed the climate control, air pump, checked my vaccuum lines and watched the actuator moove on the air box, any ideas?

What to do if your GM fan won’t defrost?

See if this fixes the problem. Many of GM’s AC control heads have a built in reset feature that when power is removed and then applied it will go through a cycle that activates all the vent doors and mode doors. It’s worth a try.

Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. Yea the problem with them astro’s is the way the damn motor is crammed into the dog house with the heat it destroys the hard plastic vacume line . I have had 5 of them and every one had this problem until you change them out with rubber lines .

See if this fixes the problem. Many of GM’s AC control heads have a built in reset feature that when power is removed and then applied it will go through a cycle that activates all the vent doors and mode doors. It’s worth a try.

Why does my a / C turn on when I Turn on the defrost?

Nothing, that is how the defrost works. When you turn on the defrost the A/C turns on automaticaly. If you mean that the air blows out of your “vent” air ducts when you turn on the A/C then you may have something stuck in your air duct plentum or a air duct plentum door is not working.

Why does my car not change off defrost?

I won’t change off defrost/floor setting I replaced the blend door actuator and did not seem to help it My car has 56000 miles. My car has an automatic transmission. Hello. You need to see if the mode door actuator is working. This actuator is on the evaporator case on the driver’s side above the gas pedal.

Can you change an A / C stuck on the floor?

A/C stuck on floor and defrost will not change on any set… I won’t change off defrost/floor setting I replaced the blend door actuator and did not seem to help it

Why does my Dodge Ram 1500 blow heat from the floor?

Dodge RAM 1500 Questions – Heat blows from vents but won’t blow from floor when put on floor mode… – CarGurus.ca You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position. The two doors that governs flow between dash vents and defrost/floor are “mode door 1” and “mode door 2.”

Why does heat not blow from the floor?

If you have air flowing only through the vents with no defrost or floor, this door is failing.

Why does my heater not change from defrost vents?

Re: Heater/ac will not change from defrost vents to any… Failure of mode and/or blend door operation most often tends to be vacuum supply issues. If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to).

Dodge RAM 1500 Questions – Heat blows from vents but won’t blow from floor when put on floor mode… – CarGurus.ca You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position. The two doors that governs flow between dash vents and defrost/floor are “mode door 1” and “mode door 2.”

What does it mean when your a / C vents don’t switch?

When you turn on the defrost the A/C turns on automaticaly. If you mean that the air blows out of your “vent” air ducts when you turn on the A/C then you may have something stuck in your air duct plentum or a air duct plentum door is not working. This type of repair involves removing the entire dash board and air ducts to just find the problem.

Why does my AC not switch from vent to floor?

Ac won’t switch from vent to floor to defrost. have the same problem? This is common when the mode actuator goes out here is a guide to help you fix the problem. Please run down this guide and report back. helpful? I had to get a new mode actuator was not that bad installing it had to pay $78.00 for the part. helpful?

Why is the vent control on my 2002 Silverado not working?

Vent control 2002 Chevy Silverado won’t switch between floor, defrost or “main”. It is stuck on “main”. Do I need to replace actuator or is there a vacuum leak somewhere?

How does the air vent work on a defroster?

The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor. On newer cars the vent direction and temperature controls are operated by a series of 3 or 4 electrical actuator motors which are adjusted by the climate control module.

Why does my air conditioner not defrost?

The air blows best out the front vents and not so well on the feet. I switch the mode to defrost and you hear it shifting over, but never gets there and then blows hard out the front vents. I don’t hear clicking like many people hear when the mode actuator is bad.

Why does the AC only blow out the defrost vent?

Click to expand… Mode door actuator for where it’s blowing. Blend door actuator for hot/cold. These are more likely culprits than the control module in the front. The rear control module being bad is more common. How can I post this message for help?

What to do when air blows out of defrost?

Try resetting the HVAC system. I had a similar problem on my 2002 Avalanche. Here’s what I did, and it worked for me. Turn the HVAC system off (turn the blower motor switch to off), and the radio off. Then turn off the truck, and disconnect the battery for 5 minutes. Reconnect the battery, then turn the ignition on, but do not start.

Click to expand… Mode door actuator for where it’s blowing. Blend door actuator for hot/cold. These are more likely culprits than the control module in the front. The rear control module being bad is more common. How can I post this message for help?

Try resetting the HVAC system. I had a similar problem on my 2002 Avalanche. Here’s what I did, and it worked for me. Turn the HVAC system off (turn the blower motor switch to off), and the radio off. Then turn off the truck, and disconnect the battery for 5 minutes. Reconnect the battery, then turn the ignition on, but do not start.

Why does AC stop blowing out the defrost vents?

After installing a new blower fan motor the ac would only come out the defrost vents. The factory vacuum check valve is very hard to get to. So i bypassed it. Now it is working like it should and ac comes out the dash vents. I do not have a vacuum reservoir installed i will have to see if i will need to add it later.

Why does air not blow out the dash vents?

The air won’t blow out the dash vents. It blows out the floor vent and the defroster vent, but it won’t change and blow out the dash vent. Any one know what I need to do to fix this problem?

Why is the a / C not coming from the front vents?

The next day I Took to the shop asking them to check vaccum first, and that didnt seem to be the issue, after tests and inspection they tell me its either the in AC panel cluster itself ( part with the buttons on it. Which seems to be working fine, I see no problems, but idk) or it could be the A/C Control Computer.

Why is the defrost not working on my GM Truck?

My airflow is stuck in the floor position no matter what setting is switched on the dash vent switch. I can’t get defrost or dash vent air to work. Fan settings do work. Also, there is no light coming on when the AC button and/or the recirculating buttons are pushed.

You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position. The two doors that governs flow between dash vents and defrost/floor are “mode door 1” and “mode door 2.”

What to do if your defroster wont blow out top vents?

If you need further assistance with defroster not working on top vents, then seek out a professional, such as one from Your Mechanic, to help you. The statements expressed above are only for informational purposes and should be independently verified.

How to change the defrost vent on a car?

Just Follow the plastic vacuum line which comes out of the pass side top rear of motor close to the alternator. You can easily see it once you pop the hood. Follow it over the brake master cylinder and then going to the front of the motor. Be careful not to pull on the vacuum lines too hard as they are brittle and crack very easily .

After installing a new blower fan motor the ac would only come out the defrost vents. The factory vacuum check valve is very hard to get to. So i bypassed it. Now it is working like it should and ac comes out the dash vents. I do not have a vacuum reservoir installed i will have to see if i will need to add it later.

Nothing, that is how the defrost works. When you turn on the defrost the A/C turns on automaticaly. If you mean that the air blows out of your “vent” air ducts when you turn on the A/C then you may have something stuck in your air duct plentum or a air duct plentum door is not working.

Re: Heater/ac will not change from defrost vents to any… Failure of mode and/or blend door operation most often tends to be vacuum supply issues. If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to).

If you have air flowing only through the vents with no defrost or floor, this door is failing.

Why does my Dodge Ram blow heat on the floor?

Dodge RAM 1500 Questions – Heat blows from vents but won’t blow from floor when put on floor mode… – CarGurus You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position. The two doors that governs flow between dash vents and defrost/floor are “mode door 1” and “mode door 2.”

Is the AC blow out of the defrost vents?

Hi Dave, I have a Jeep Liberty 2012, the AC vents blow on the floor and defrost but not the chest areas in the vehicle. Is there an inexpensive way to … read more Vocational, Technical or Tra… Grand Cherokee: Jeep 2001 GC. Heater is not blowing hot from Jeep 2001 GC. Heater is not blowing hot from certain vents.

A/C stuck on floor and defrost will not change on any set… I won’t change off defrost/floor setting I replaced the blend door actuator and did not seem to help it

Can you turn the defrost knob back to feet?

I can turn the knob to defrost, then it springs back to feet/defrost but still only comes out of the front dash vents. I can turn the knob to every other setting and the knob will stay there but no matter what it only comes out of the front dash vents.

No heat to feet or defrost. Before replacing Heater Control Unit, it would only blow hot air from front vents- With this replacement it will now change from cold to hot and the air flow pressure does change from the front vents when changing the setting dial but there is still no air at all to feet and defrost.

Can a / C only blow out of defrost vent?

Problem is no matter what setting I put it on it still blows out of the windshield defrost vents. Has anyone had this problem before?

Can a Ford F350 heater change to any other vents?

Heater/ac will not change from defrost vents to any other vents on my Ford F350. AC works but comes out of defrost only Clicking this will make more experts see the question and we will remind you when it gets answered. You can’t post conmments that contain an email address. An expert that got 10 achievements. An expert that got 5 achievements.

Heater/ac will not change from defrost vents to any other vents on my Ford F350. AC works but comes out of defrost only Clicking this will make more experts see the question and we will remind you when it gets answered. You can’t post conmments that contain an email address. An expert that got 10 achievements. An expert that got 5 achievements.

Is the air conditioner blowing out of the vents?

The air conditioning in my cadillac doesn’t blow out of the vents on the dash. But it blows air out of the side vents on the doors. How do I use the self diagnostics feature on my air conditioner?

Why is air not blowing out of the dash vents?

A few different items can cause the air to not blow out of the dash vents. The most common are a blend door or a control switch.

Why does AC come out the dash vents?

The factory vacuum check valve is very hard to get to. So i bypassed it. Now it is working like it should and ac comes out the dash vents. I do not have a vacuum reservoir installed i will have to see if i will need to add it later. Don’t forget to like, comment, share and subscribe to my channel. Loading…

Why is there no air from the floor vents?

If its electric you may simply have a blown fuse or it could be a bad actuator, if its vacuum you would need to look for leaks in the system. which could be in the lines to the actuator or the actuator itself . Hope this helps Was this answer helpful? I have the same problem and actually there are 3 of those things.

Why is my Ford F-250 stuck in defrost?

The suction system not only controls air zone valves, but also 4X4 activation. Typical vacuum leaks, like old lines are often the problem, but there is one last component that everyone participating on automotive help forums fails to mention when troubleshooting this trouble prone system, the electric vacuum solenoid valve. Loading…

Can a climate control fan only blow defrost?

SilveradoSierra.com • Fan Only Blows Defrost, Won’t Change To Floor Or Vent. : Climate Control Fan Only Blows Defrost, Won’t Change To Floor Or Vent.

What to do if your truck fan only blows defrost?

Honestly, don’t know if your control head has a built in recal feature, but a cheap way to find out. Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. When you reattach the battery and crank the truck dont touch anything for five minutes. Then shut the truck off, crank it and see if its fixed.

Why does my car defrost when I Turn on the AC?

This is a very common problem on vehicles with vacuum actuated HVAC controls. The plastic vacuum lines break and the system defaults to defrost. This is a very common problem on vehicles with vacuum actuated HVAC controls. The plastic vacuum lines break and the system defaults to defrost. Skip navigation Sign in Search Loading… Close

Why does my air conditioner keep going past the defrost setting?

Must be a spring issue because one day I said **** it and kept cranking it past the defrost setting clockwise as hard as I could over and over trying to force it and the spring behind the dial popped and corrected itself.

Why does my AC blower blow out the vents?

If it does, it’s almost certainly due to a vacuum leak. Acceleration does not affect it. If I set the blower on “high” or “Max AC” it will only blow out of the defrost vents.

The next day I Took to the shop asking them to check vaccum first, and that didnt seem to be the issue, after tests and inspection they tell me its either the in AC panel cluster itself ( part with the buttons on it. Which seems to be working fine, I see no problems, but idk) or it could be the A/C Control Computer.

Is the AC blowing out of the vents?

The main vent of the vents that faces the passengers blows out nothing. The speed of the ac works. The heat also works. I check my cabin filter, replace the ac control knob or panel and still nothing works. when changing from ac blowing to the face and leg to defrost u can here it switch but no ac comes out of the front vents.

Where is the blower motor resistor located on a Ford Escape?

In the 2008-2011 Ford Escape, the resistor is located behind the glove box on top of the HVAC unit air duct. It’s held by two screws and is easy to replace. See the photo. In the 2008-2011 Ford F150 the blower motor resistor is also located behind the glove box, but is installed in the right side of the plastic air duct.

Why is my a / C blowing hot air out of the vent?

Based on your description, it is possible your fresh air/recirculating motor is faulty, as it sounds like it is only pulling in hot air. We recommend a trip to an A/C specialist to check on the motor and make sure it is connected properly. Thank you!

What to do if your truck fan won’t change?

When you reattach the battery and crank the truck dont touch anything for five minutes. Then shut the truck off, crank it and see if its fixed. Not touching anything lets it go through its relearn process. Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. I tried taking the neg off the battery but it didn’t fix it.

When does the F-150 radiator fan kick on?

The 2009-2014 Ford F-150 was introduced for the 2009 model year as an update of the Ford full-size truck platform. 2010 Ford F150, Radiator fan seems to be running on high more than it should. Fan kicks on about 30 seconds after vehicle is started and is extremely loud.

Why is my Ford F150 making a noise?

Drivers have complained about a chattering sound in the rear part of the Ford F150, specifically the 1990-96 models. The noise occurs during soft turns in the vehicle after driving at high speeds. The problem came in an insufficient friction modifier or a faulty Traction-Lok differential.

Are there any problems with the Ford F-150?

Check out our Ford F-150 overview to see the most problematic years, worst problems and most recently reported complaints with the F-150.

What causes a Ford F150 engine to flare up?

More commonly in the 1994-95 models, the TR/MLP sensor would be faulty and cause the engine to flare up when the truck switched to fourth gear. Ford’s solution was to fix the distorted valve plates. 3. Issue: Ball joints In the 1990-96 models, the ball joints would be ruined if exposed to water.

What causes a defroster door to get stuck?

In some cases an electrical motor can burn out or the gears inside the actuator can break causing the defroster door to get stuck. A climate control system can stop working after a battery replacement as the control prompt of the system is lost and needs to be rebooted by removing the defroster/heater fuse for a period of time and then reinserted.

If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.

In some cases an electrical motor can burn out or the gears inside the actuator can break causing the defroster door to get stuck. A climate control system can stop working after a battery replacement as the control prompt of the system is lost and needs to be rebooted by removing the defroster/heater fuse for a period of time and then reinserted.

The defroster is part of the heater and air conditioner system which is housed inside of the heater plenum. The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor.

Is there issue with auto climate control not changing from vent to vent?

Has anyone had an issue with the auto climate control not changing from vent to vent? Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. Pull the negative battery cable and re-install, making sure it is very tight (also check the positive to make sure it is tight). See if this fixes the problem.

If its electric you may simply have a blown fuse or it could be a bad actuator, if its vacuum you would need to look for leaks in the system. which could be in the lines to the actuator or the actuator itself . Hope this helps Was this answer helpful? I have the same problem and actually there are 3 of those things.

Why does heat not transfer from vent to floor?

heat won’t transfer from vent to floor when put on floor heat blows from defrost. You most likely have an air door actuator problem. It’s stuck in the vent position and can’t shift to the floor position.

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Ruth Doyle