air vent problems

Joey791 · 01-18-2004, 12:32 AM

1st let me say i love this forum and i wish i had found this forum before i did most of my modifications on my jeep... Great jeep experts here!!! Anyways my question is my A/C works fine but the blower seems to get stuck in the Defrost position. I thought maybe a fuse was blown but i can't find the answer... JEEP FORUM to the rescue...........again

Scootr · 01-18-2004, 11:07 AM

Could be a vacuum problem with the actuator that selects the position.

davenjeip · 01-18-2004, 12:17 PM

Quote:

Originally Posted by Scootr

Could be a vacuum problem with the actuator that selects the position.

I agree. Defrost is the default setting and when you aren't getting the vacuum, it goes to defrost.

Joey791 · 01-19-2004, 11:40 PM

OK? i'm no mechanic soooooo where is the actuator and how do i fix it. Thanks for the help!!!

Tinker · 01-20-2004, 12:14 AM

my 97 is suffering the same symptoms, all the air comes out the defrost ductting and its not very warm either.I will be watching this thread as well. Thom

GoTopless · 01-20-2004, 12:22 PM

Quote:

Originally Posted by fineswinecycles

my 97 is suffering the same symptoms, all the air comes out the defrost ductting and its not very warm either.I will be watching this thread as well. Thom

same here

............................

dagger55 · 03-30-2004, 08:00 PM

Quote:

Originally Posted by Joey791

1st let me say i love this forum and i wish i had found this forum before i did most of my modifications on my jeep... Great jeep experts here!!! Anyways my question is my A/C works fine but the blower seems to get stuck in the Defrost position. I thought maybe a fuse was blown but i can't find the answer... JEEP FORUM to the rescue...........again

By chance did you fix the problem with the blower? I have the same issue with my 99TJ.

ncb76 · 03-30-2004, 10:50 PM

Quote:

Originally Posted by fineswinecycles

my 97 is suffering the same symptoms, all the air comes out the defrost ductting and its not very warm either.I will be watching this thread as well. Thom

If you have a slide type selector for the vents, check the cable. It can get a kink in it which makes it hard to move. Remove the assembly and use a pair of needle nose pliers to get it back in shape.

Kris B Krunch · 03-31-2004, 12:59 AM

Quote:

Originally Posted by fineswinecycles

my 97 is suffering the same symptoms, all the air comes out the defrost ductting and its not very warm either.I will be watching this thread as well. Thom

I've got the same problem, exept mine still does hot air. I can either have the fan off, or in ANY of the other positions it's in defrost. Any suggestions on how to fis it? The slider seems to move around fine, but doesn't make that air sorta noise that it used to, if you know what I mean.

paul olllllllo · 03-31-2004, 06:42 AM

Quote:

Originally Posted by Kris B Krunch

I've got the same problem, exept mine still does hot air. I can either have the fan off, or in ANY of the other positions it's in defrost. Any suggestions on how to fis it? The slider seems to move around fine, but doesn't make that air sorta noise that it used to, if you know what I mean.

I sure hope someone here can help as i have the same problem, only my air location will change from time to time. for example i set the air to come out the panel vents and i will stop at a light and the air will start to come out of the defroster, then when i accelerate it will change back to panel vents. i have been told it is probably a vacuum issue but i checked all my vacuum lines and they appear to be connected properly so i dont know what else to look for. if anyone can help if sure would be appreciated

thanks, paul.

powerstroke01 · 03-31-2004, 10:51 AM

Mine is doing all of the above..

NV Jeep Girl · 08-11-2004, 11:11 AM

Hi there,

I am having the same problem, everything is coming out of the defroster vents, not the front vents. Anyone find a solution?

Thanks!

Tinker · 08-11-2004, 11:20 AM

Mine wound up being a broken vaccuum line under the battery going into the vaccuum canister. Once I repaired the break all was well again. Hope this helps. Thom

BNovak · 08-11-2004, 11:32 AM

I had the same thing, and took about a week to find the root of the problem.

Question that may help further diagnose the problem though...

Does your heater box make a "clunking" sound when you accelerate or brake? If it does, than most likely you have a broken control arm on one or more of the heater duct rods.

If it doesn't, check the vacum actuators. So here's what I would do.

First - Let's look at the vacum actuators.

1 - Get your head underneath the paneling on the drivers side - this is not fun, but you'll see where I'm going once you get there.

2 - there are 3 silver "cans" with 2 hoses on each one, and a lever coming out of one end - these are your actuators

3 - Start the engine, set the brake and find a friend - you can do this by yourself but it's a PITA.

4 - Turn the fan on LOW

5 - Move the selector lever from one setting to the next SLOWLY! Give it time to settle. As you move the control, the "cans" should move in and out, but they don't all move at the same time for each setting (top one is for the defroster, I think the bottom is for the floor vents, and you can guess what the middle does.)

6 - Check all the selector positions - if none of them move, then you have a vacum leak. If this is the case, better go find a vacum gun and figure out which one is broken.

If by chance you don't have a vacum leak, it COULD be the actuator cans themselves - they have a rubber diapraghm that potentially could break and cause it to not work.

Alright, if you've determined that the actuators work, time for the tough one.

This is to check the actual control arms.

1 - take off the plastic panel under the steering wheel
2 - take off the metal plate behind that
3 - find a flashlight (worklight on the floor of the jeep works too)
4 - Turn on the engine
5 - Move the control slider to the different settings, and watch the moevement of the arms coming off the silver cans.
6 - if the arms move, but the black plastic levers don't, they are broken.
7 - to remove a broken plastic thingy, there's two methods
7A - take the silver vacum actuator off, and grab the plastic arm with a pair pf pliers and pull really really hard straight out. It'll pop off eventually
7B - if it's like mine was, then the arm broke off inside where you cant grab it it get's even tricker. Get a really long decking screw or similar and drive it straght in. Grab the screw with the pliers and pull
8 - finding a replacement is tough - there's a jeep recycler on line (can't remember who it was, I'll go look when I get home) that MAY have these. If you go to the dealer, they'll look at you like you have 4 heads and try and get you to buy a whole new "Blender Box" which is what the heating system is refered to. DON"T DO IT. You only need the plastic arm, but even that will set you back $25 from a recylcer.

For some reason, these plastic things break all the time, and Jeep doesn't offer an "Off the shelf" replacement part. Stupid stupid stupid. If I had an injection molder, I'd start making them and selling them!

Hope this helps.
--BN

jtstj · 08-11-2004, 01:07 PM

Great info!! Upon researching in a service manual, I also found a 4th can. It is for the Recurculating door (on AC modles only). I also found several warnings about the AirBag system. So be careful when poking around, especially under the passenger side.

01-19-2004, 11:40 PM	#4
Joey791 Registered User Join Date: Nov 2003 Posts: 25 Profile Gallery Classifieds My Jeeps	OK? i'm no mechanic soooooo where is the actuator and how do i fix it. Thanks for the help!!! __________________ 1999 chilli pepper red TJ.

03-31-2004, 10:51 AM	#11
powerstroke01 Registered User Join Date: Jan 2004 Location: Ahwahnee, California Posts: 293 Profile Gallery Classifieds My Jeeps	Mine is doing all of the above.. __________________ 1997 BLACK TJ Sport. 5spd, D44, 33X12.50s, 4.56, 3"susp lift, 1"bl, winch, ARB. Blah blah blah.

08-11-2004, 11:32 AM	#14
BNovak Registered User Join Date: Jun 2004 Location: Portland, Oregon Posts: 2,081 Profile Gallery Classifieds My Jeeps	I had the same thing, and took about a week to find the root of the problem. Question that may help further diagnose the problem though... Does your heater box make a "clunking" sound when you accelerate or brake? If it does, than most likely you have a broken control arm on one or more of the heater duct rods. If it doesn't, check the vacum actuators. So here's what I would do. First - Let's look at the vacum actuators. 1 - Get your head underneath the paneling on the drivers side - this is not fun, but you'll see where I'm going once you get there. 2 - there are 3 silver "cans" with 2 hoses on each one, and a lever coming out of one end - these are your actuators 3 - Start the engine, set the brake and find a friend - you can do this by yourself but it's a PITA. 4 - Turn the fan on LOW 5 - Move the selector lever from one setting to the next SLOWLY! Give it time to settle. As you move the control, the "cans" should move in and out, but they don't all move at the same time for each setting (top one is for the defroster, I think the bottom is for the floor vents, and you can guess what the middle does.) 6 - Check all the selector positions - if none of them move, then you have a vacum leak. If this is the case, better go find a vacum gun and figure out which one is broken. If by chance you don't have a vacum leak, it COULD be the actuator cans themselves - they have a rubber diapraghm that potentially could break and cause it to not work. Alright, if you've determined that the actuators work, time for the tough one. This is to check the actual control arms. 1 - take off the plastic panel under the steering wheel 2 - take off the metal plate behind that 3 - find a flashlight (worklight on the floor of the jeep works too) 4 - Turn on the engine 5 - Move the control slider to the different settings, and watch the moevement of the arms coming off the silver cans. 6 - if the arms move, but the black plastic levers don't, they are broken. 7 - to remove a broken plastic thingy, there's two methods 7A - take the silver vacum actuator off, and grab the plastic arm with a pair pf pliers and pull really really hard straight out. It'll pop off eventually 7B - if it's like mine was, then the arm broke off inside where you cant grab it it get's even tricker. Get a really long decking screw or similar and drive it straght in. Grab the screw with the pliers and pull 8 - finding a replacement is tough - there's a jeep recycler on line (can't remember who it was, I'll go look when I get home) that MAY have these. If you go to the dealer, they'll look at you like you have 4 heads and try and get you to buy a whole new "Blender Box" which is what the heating system is refered to. DON"T DO IT. You only need the plastic arm, but even that will set you back $25 from a recylcer. For some reason, these plastic things break all the time, and Jeep doesn't offer an "Off the shelf" replacement part. Stupid stupid stupid. If I had an injection molder, I'd start making them and selling them! Hope this helps. --BN __________________ '97 Forest green. ~6" total lift, 8.8, etc. 36" TSL's, winch. You get the drill.

08-11-2004, 11:11 AM	#12
NV Jeep Girl Registered User Join Date: Mar 2004 Location: Reno, NV Posts: 1 Profile Gallery Classifieds My Jeeps	Hi there, I am having the same problem, everything is coming out of the defroster vents, not the front vents. Anyone find a solution? Thanks!