When there is a problem in the vent system it defaults to defrost setting. Check the doors & vac supply
that usually indicates a vacuum leak which causes the system to go into default mode, which is defrost.
If the vents stop blowing when gas is applied, it is likely a vacuum problem. The vent system is controlled by vacuum, so when the engine is under load, there isn't enough vacuum to run the vents. How you test this is when the problem occurs, the fan will still be blowing air, however the flow of air will be out your window defrost vents at the top front of the dash. On a 1995 vehicle, it's likely just some of your vacuum lines are broken, and need replaced or repaired.
If this is the condenser that is frozen, you have a problem with the defrost cycle. There are 2 things that need to be checked, the defrost sensor and the defrost control board. More than likely it is the defrost control board that is the problem and of course that is the more costly of the 2.
If the temperature cannot be changed for any of the direction settings, e.g., defrost, vents, floor, then the problem is very likely to be the blend door actuator motor.See "Related Questions" below for more
Found problem, intermittent short circuit problem in turn signal switch, replaced switch, problem went away.
Hi, I had this problem on a 2000 Alero. Had to disconnect the battery to shut it up. G.M. replaced the horn relay to aleviate the problem. Duke
If you can Not change the location of the air flow to the different outlets (defrost, dash, floor, etc) That sounds like a mode door problem or a mode door control knob.
Where the air blows out control are vacuum operated.A more common problem is when the air is stuck on defrost only.The cause is essentially the same, so check out the "Related Question" below for where to go next
Dodges are good for blowing fuses. If that is not it, the fan switch might need replaced.
the failure is with the "blend door" very expensive unless you are mechanical.
I own a 1994 acura integra and the heater/air conditioning blower is not working, I can not defrost my windows and the heat does not blow. What is wrong and how can the problem be fixed.
You need to check the vacuum lines for the a/c system for leaks, breaks and loose ones first.......
It doesn't sound like a problem the way you worded it. If it stopped to defrost all the time it wouldn't keep anything cold
Have you checked to see if your 12V dc relay under the hook is working properly?
I had the same code thrown in my 97 eclipse gsx and i replaced the o2 sensor that's after the CAT and that solved the problem
It could be electical like a fuse, but I had a problem on my 2000 Astro that was caused by a rubber vaccuum line that was split. I replaced it for about 2 bucks and it corrected the problem. Hope this helps
The default for heaters is to go to defrost if there is a problem in the system. You will have to get under the dash to find the problem. Probably best to take it in as they can get tricky without diagrams depending on the system
Hi have same problem my Montero 2001 serial 99F60514 model MR563520
If defrost is on it could be your compressor going bad. See what happens when you leave off defrost or disconnect your compressor. It only controls defrost and air conditioning. I had the same problem
Your car seems to be getting too much fuel, is it computer controlled?
Cadillacs are notorious for blowing head gaskets. You may want to look into that.
no defrost on left side of car and antifreeze draining on right side of car. What is the problem
When there is a problem with the vent system it dfaults to the defrost setting. Sounds like you have a problem in the doors that direct the air flow.
my Chevy cobalt 2005 keeps blowing the fuse everytime i put my windows up or down i had the door wireing replace a new window motor replaced new switch and it still blows the fuse what can the problem be