Vacuum Lines. I had the same problem and it was due to cracked vacuum lines. Listen for some hissing under the hood and you might be able to find the source of the problem. Mine was right around the battery....................As this may be the problem your should first check under your passenger side right under the glove box you might have to take a interior trim plate and you can check the door a vaccum door and manually move it and you can get air out of your window defroster and possiblt getting it switched over and get it working if not you have two actuators there you can get replaced.
does fan door motorized or on a vaccuum line when you switch from AC to defrost?
If you feel no air blowing at all (when you are not moving) then your fan is not blowing. If it is blowing air, and it is cold, when the heater is on, then most probably your heater core is leaking, or is clogged. These are easily replaceable and go bad all the time in older cars.
The fastest way to defrost a windshield is to turn the defrost vent on without heat or simply open the windows. Another option is to warm the inside of the car by turning the heater on.
no heat to front window went defrost is on
on the dash below the windshield.
That means either you have air in your heater core or your heater core is being bypassed
Yes, the ac will run in the defrost position to dry the windshield.
Start driving with your air conditioning on defrost, the AC will defog the windshield but you need to be moving.
When there is a problem in the vent system it defaults to defrost setting. Check the doors & vac supply
The AC on a 1998 Dodge Ram 1998 will only be blowing out the defrost vent if the air handler is not set properly. This can result from a piece of debris getting stuck or a faulty flap.
Remove frost or ice from (the windshield of a motor vehicle).Thaw (frozen food) before cooking it.
Yes, the windshield defroster will turn the A/C compressor on.
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.
you have a vac. leake or the oneway check valve is not working.....
cooling fan relay short or bypassed or defrost or ac selector on
Take the defrost panel off the dashboard and look through the windshield above the passenger side air bag with a bright flashlight. There will be a white box that says "forward" with an arrow, the code is on that box in big letters
Look for a broken vacuum line coming out near the ac lines on the passenger side under the hood.Look for a broken vacuum line coming out near the ac lines on the passenger side under the hood.
If it only does this after a rain, chances are you have a leaking windshield. Or the aircond. drain is clogged, even if you are only using the defrost with heat the air-cond. runs with the defrost.
You have a vacuum leak causing your vents to switch from dash to defrost.
Steam shows up on the inside of the windshield after shut down if you leave it on defrost. Damp carpet near top right of passenger floor or dripping antifreeze near the right front tire near firewall, jja
The blower motor fuse has blown or the blower motor itself has blown. Change the fuse or replace the blower motor itself and you should be good.
If central air conditioner turns on but is not blowing through the vents, check the filter. If it is dirty, change it. Change the thermostat into cool, this will defrost the air conditioner.
On my 1995 Ford Explorer when the defrost position is selected , and the temperature knob is set in the red area to get heated air to defrost the windshield , the A/C compressor will cycle on and off to help dehumidify the air, but the compressor ONLY cycles on and off in the DEFROST POSITION ( sorry if I'm misinterpretting your question )
that usually indicates a vacuum leak which causes the system to go into default mode, which is defrost.
With many vehicles, if the defrost mode is on, the ac will continue to run. This helps to clear the inside windshield from moisture.