Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

HVAC Cutting in and Out

Thread Tools
 
Search this Thread
 
Old 02-02-2014 | 03:01 PM
  #1  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default HVAC Cutting in and Out

Hey Guys, So I have a 1999 XJ Sport and seem to be having problems with my HVAC. I did try to look this up before posting but didnt really see any good responses.
The problem is that sometimes my HVAC system just doesnt work, meaning there is no air blowing through the Jeep at all. I have tried this on all settings, hot or cold, AC settings or normal settings, all the different fan speeds, and nothing seems to put it on. It never seems to happen in a pattern either. Sometimes in the morning it just doesnt work, and other times after driving for a little bit it will just cut out. When it would snow, i would make sure that the cowl was clean because I have heard that's where the HVAC unit is. Im just wondering if you guys have any ideas of what this can be. It could get a little scary when you are driving in the cold with gloves on and your windshield starts to fog up with no defroster to put on!
I dont really have access to a garage or have the time to guess and check at the moment but maybe if you guys have some ideas that maybe if i have some free time i could try that would be great!
Old 02-02-2014 | 03:22 PM
  #2  
Roler's Avatar
CF Veteran
 
Joined: Jan 2012
Posts: 3,170
Likes: 311
From: Australia
Year: 1997 (RHD)
Model: Cherokee (XJ)
Engine: 4.0 ltr
Default

So, you have no air at all, in any setting?
Blower motor related issue?...since doesn't sounds like a blend door or vent (vacuum) issue. There is also a blower motor resistor...

Last edited by Roler; 02-02-2014 at 03:27 PM.
Old 02-02-2014 | 03:29 PM
  #3  
prcherokee's Avatar
Senior Member
 
Joined: Mar 2012
Posts: 615
Likes: 0
From: FL.
Year: 2000
Model: Cherokee
Default

http://www.cherokeetalk.com/forum/f6...acement-11133/
Old 02-02-2014 | 03:36 PM
  #4  
Roler's Avatar
CF Veteran
 
Joined: Jan 2012
Posts: 3,170
Likes: 311
From: Australia
Year: 1997 (RHD)
Model: Cherokee (XJ)
Engine: 4.0 ltr
Default

and the write-up to match it...yay
Old 02-02-2014 | 04:03 PM
  #5  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default

Thanks for the quick responses. This week I will look online to get a BMR and try replacing it this upcoming weekend.
Old 02-02-2014 | 04:04 PM
  #6  
CCKen's Avatar
CF Veteran
 
Joined: Aug 2010
Posts: 8,357
Likes: 90
From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Default

Originally Posted by XJ914
Hey Guys, So I have a 1999 XJ Sport and seem to be having problems with my HVAC. I did try to look this up before posting but didnt really see any good responses.
The problem is that sometimes my HVAC system just doesnt work, meaning there is no air blowing through the Jeep at all. I have tried this on all settings, hot or cold, AC settings or normal settings, all the different fan speeds, and nothing seems to put it on. It never seems to happen in a pattern either. Sometimes in the morning it just doesnt work, and other times after driving for a little bit it will just cut out. When it would snow, i would make sure that the cowl was clean because I have heard that's where the HVAC unit is. Im just wondering if you guys have any ideas of what this can be. It could get a little scary when you are driving in the cold with gloves on and your windshield starts to fog up with no defroster to put on!
I dont really have access to a garage or have the time to guess and check at the moment but maybe if you guys have some ideas that maybe if i have some free time i could try that would be great!
Are you saying that the blower does work but intermittantly it cuts out?
Old 02-02-2014 | 04:05 PM
  #7  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default

Originally Posted by Roler
So, you have no air at all, in any setting? Blower motor related issue?...since doesn't sounds like a blend door or vent (vacuum) issue. There is also a blower motor resistor...
Well sometimes it works fine and sometimes it decides to just not blow at all. Maybe that's the blower motor resistor on it's way out..
Old 02-02-2014 | 04:06 PM
  #8  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default

Originally Posted by CCKen
Are you saying that the blower does work but intermittantly it cuts out?
Yep. Sometimes it'll work when I start up the jeep, sometimes it won't work on startup. Sometimes it just cuts out while driving but sometimes it just stays on
Old 02-02-2014 | 04:13 PM
  #9  
CCKen's Avatar
CF Veteran
 
Joined: Aug 2010
Posts: 8,357
Likes: 90
From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Default

Originally Posted by XJ914
Well sometimes it works fine and sometimes it decides to just not blow at all. Maybe that's the blower motor resistor on it's way out..
Blower motor resistor blocks usually have a hard failure. That is, it works or it doesn't work, and in most cases the blower will operate in only in the high speed setting.

An intermittant blower may mean that the blower is starting to fail.

There are other areas that need attention on this sort of problem, and that is the blower motor resistor block connector may be melted (common). It would be a good idea to access the resistor and inspect the connector.

Don't just shotgun a resistor until you've chcked things out.
Old 02-02-2014 | 07:21 PM
  #10  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default

Originally Posted by CCKen
Blower motor resistor blocks usually have a hard failure. That is, it works or it doesn't work, and in most cases the blower will operate in only in the high speed setting. An intermittant blower may mean that the blower is starting to fail. There are other areas that need attention on this sort of problem, and that is the blower motor resistor block connector may be melted (common). It would be a good idea to access the resistor and inspect the connector. Don't just shotgun a resistor until you've chcked things out.
Thanks for the info. How long do you think it takes to get to the blower motor resistor and check it out? From the other thread someone posted in here it seems like it's just behind the glove box
Old 02-02-2014 | 08:00 PM
  #11  
CCKen's Avatar
CF Veteran
 
Joined: Aug 2010
Posts: 8,357
Likes: 90
From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Default

Originally Posted by XJ914
Thanks for the info. How long do you think it takes to get to the blower motor resistor and check it out? From the other thread someone posted in here it seems like it's just behind the glove box
It is behind the glove box.

There's a kick panel protecting it, and other goodies.

There's four screws holding it on. The top of the panel has slots for the top two screws so all youhave to do is loosen them enough to pull the panel down. The bottom two screws have to be removed. Time wise? It's your call...15 minutes at the most if it's daylight and not bitter cold.

Edit: Here's a drawing of the kick panel.

Name:  jpgKickPanel.jpg
Views: 53
Size:  28.2 KB

Last edited by CCKen; 02-02-2014 at 08:14 PM.
Old 02-09-2014 | 03:52 AM
  #12  
99ZombieSport's Avatar
Junior Member
 
Joined: Nov 2013
Posts: 31
Likes: 0
Model: Cherokee
Default

Mine does the same thing, I have to pop the hood and play with the wire going to the blower motor. It is on the passenger side in the fire wall. I am trying to find some kind of part number or name on this to replace it. Might just have to make my own.
Old 02-09-2014 | 01:33 PM
  #13  
XJ914's Avatar
Thread Starter
Junior Member
 
Joined: Oct 2013
Posts: 45
Likes: 0
From: Westchester, NY
Year: 1999
Model: Cherokee
Engine: 4.0L Straight 6
Default

Originally Posted by 99ZombieSport
Mine does the same thing, I have to pop the hood and play with the wire going to the blower motor. It is on the passenger side in the fire wall. I am trying to find some kind of part number or name on this to replace it. Might just have to make my own.
Think you can get a picture of the wire and where it is?
Old 02-09-2014 | 03:57 PM
  #14  
99ZombieSport's Avatar
Junior Member
 
Joined: Nov 2013
Posts: 31
Likes: 0
Model: Cherokee
Default

Not good pics but once you see it you will know what I am talking about.
Attached Thumbnails HVAC Cutting in and Out-photo-1.jpg   HVAC Cutting in and Out-photo-2.jpg  
Old 02-09-2014 | 04:00 PM
  #15  
99ZombieSport's Avatar
Junior Member
 
Joined: Nov 2013
Posts: 31
Likes: 0
Model: Cherokee
Default

Hmm Westchester, your not to far from me. I'm up in Sullivan county.



All times are GMT -5. The time now is 08:46 AM.