A/C problem with 1999 malibu


acprob
06-04-2003, 08:46 AM
This problem of mine is getting expensive and the GM guys cannot find the problem. The light on the button that shows that the AC is on sometimes flickers and goes out then comes back on after a few seconds, and this happens randomly. When the light is off there is no cooling affect but the fan is still blowing. I have brought it in 4 time to the dealers and the last time they spent 3 hours on it, checked it all over and only put dye in it. Any one else have this problem?

twallacenc
06-24-2003, 06:03 AM
I recently purchased a 1998 Malibu that is giving the same trouble. I have noticed that it most often happens when I change the fan speed setting. I found that when this occurs, I can gently wiggle the fan speed control knob back and forth a little and the a/c light comes back on and begins to cool again. I have not had time to look into the root cause of this problem, but suspect a cold solder joint on the circuit board that opperates the fan speed. I could only suggest that you remove this unit and check for bad solder joints yourself or have someone look for you. Otherwise, you could buy a new or used assembly and install yourself. I assume this is probably an expensive part, but is probably easy to change out. There are alot of places on the net that sell discounted original GM parts. You might have some luck browsing through a junkyard and buying one used, although, you might end up with the same problem with a used one. I feel certain this control set-up was used with numerous GM models, so if you're looking in the junkyard it would pay you to try and find the newest car you can. I'll post more on this subject as I discover information.

twallacenc
06-24-2003, 08:32 PM
I found a new HVAC control for the Malibu at "newgmparts.com" and it was alot less expensive than I thought ($119). I don't think I would bother with one from a junkyard. I still plan to take mine apart and see if I can repair it before I purchase a new one.

acemech129
07-10-2003, 09:21 PM
problem in a/c control button portion of control head i have replaced several dozen of these controls for this problem.

speeder94
07-10-2003, 09:24 PM
put some freon a ri34 recharge only cost about 10$

bobdoles
05-22-2004, 01:59 PM
I am having the same problem with my 99 LS. It just started, just wondering if i need to check the freon or replace the a/c controls on the dash. The a/c switch flicks off and on.

Thanks

wpbharry
05-23-2004, 01:25 AM
This is a normal problem with '97-'99 (and possibly later) Malibus. The problem is NOT in the A/C unit. It's what GM calls the "control module". Basically a cheap dash part. Mine has been replaced three times, on my '98 LS, all under GMPP, so have no idea about the cost. The A/C is fine; it's the dash unit. GM is known for excellent A/C. If only the dash switch cooperated.....

bobdoles
05-24-2004, 09:25 AM
so what part to i need to replace. I have already replaced the resistor that fixed the 1 and 2 blower motor problem. If you could please be more specfic on the part and were it is located.

Thanks you

wpbharry
05-24-2004, 01:04 PM
Sorry, dude, it's not that I'm mechanically-challenged, it's GMPP. I take the POS in, they give me a rental, and I'm outta there. Then, when it's fixed I ask a lot of questions, and it's the "control module".

Maybe a GM mechanic can fill you in on more details. E2helper???

bobdoles
05-24-2004, 10:07 PM
so when you say control module. Is that like the hole a/c control's on the dash. If so, is it hard to replace.

Thanks for your help wpbharry.

wpbharry
05-24-2004, 11:52 PM
As I said before, I really have no clue what they fix. The car goes in, I go out, and it's the same "BS" every time. Was trying my best to get a reply from "someone-in-the-know", but remember, this is Memorial Day weekend coming up, so folks might be out of town....

bobdoles
06-02-2004, 11:08 AM
bumb

breugel
06-07-2004, 10:07 PM
Mine does the same thing.

bobdoles
06-08-2004, 09:09 AM
just wondering if any body knows were the control module is and how hard it is to replace it. any help would be greatly app.

LEYLAND
06-09-2004, 09:56 PM
I have a 98 Malibu and mine is doing the same thing since last year. I just ignor it.

bobdoles
06-13-2004, 10:03 PM
i live in florida. It is really hot right know. Ignoring it is hard to do in Florida. I don't think anybody has fixed this problem. oh well thanks anyway.

sadavid2000
06-22-2004, 10:00 AM
I have a 98 malibu ls and had the same problem. They replaced the control under warranty but I didn't ask specifics.

Dan McNerney
07-06-2004, 03:13 PM
The HVAC control module is a one piece plastic unit consisting of the Blower speed switch, variable temp setting, air delivery position switch, as well as the 4 buttons underneath these switches. It is located directly under the radio. The following link, which is really for replacing the radio, will tell you how to remove the trim around it as well as show the control module without the trim installed.

http://www.carstereohelp.com/stereoremovalChevyMalibuStrR.htm

Dan McNerney
07-06-2004, 03:37 PM
Remove the ignition key trim cover. Pry off with a flat bladed tool.
Gently pull the plate (1) rearward in order to disengage the retainers from the instrument panel (3).
Disconnect the cigarette lighter (2) connector.
Disconnect the cigarette lighter (2) electrical connector.
Remove the trim plate (1).

donsixtyfive
07-07-2004, 03:02 PM
The control module is the whole cluster of buttons and dials for the climate system.

Easy to replace, the trim around the whole center stack just snaps off. Then remove the two small screws holding the panel in. Takes about 15 minutes or so, depending on your ability. the part is about $159 from GM, not sure I'd buy from an aftermarket since GM may have updated the part to fix recurring problems and an aftermarket may not have.

Hope it helps.

george_malibu
06-09-2005, 06:48 AM
Sounds like a recall dont you think? My '98 is doing it too and it was replaced in 01. That one too does the blinky blinky on off.

LAW SUIT!!!!!

BeatnikTermite
06-09-2005, 07:02 AM
Do not replace the head unit. The problem is almost assuredly dirty contacts. There have been many people on this board, including myself, that had the same problem. Remove the trim, remove the unit, clean it as shown in the link below, and it should work just fine. I have done this and have been flicker-free for over six months, including the past week where it has been 85 degrees, with nearly 100% humidity. Plus this fix is free.

Go to:
http://www.automotiveforums.com/vbulletin/showthread.php?t=324015

Eyebolt
06-09-2005, 07:24 AM
Do not replace the head unit. The problem is almost assuredly dirty contacts. There have been many people on this board, including myself, that had the same problem. Remove the trim, remove the unit, clean it as shown in the link below, and it should work just fine. I have done this and have been flicker-free for over six months, including the past week where it has been 85 degrees, with nearly 100% humidity. Plus this fix is free.

Go to:
http://www.automotiveforums.com/vbulletin/showthread.php?t=324015


I guess I found what fix I'm gonna try first...my wife's had this problem for a while, but has gotten progressively worse in her 2000 Mailibu. She's just been complaining about it agian because the temps here in Michigan have been up in the 90's lately with high 90-100% humidity...it's like August in June...

breugel
06-09-2005, 09:28 AM
Do not replace the head unit. The problem is almost assuredly dirty contacts. There have been many people on this board, including myself, that had the same problem. Remove the trim, remove the unit, clean it as shown in the link below, and it should work just fine. I have done this and have been flicker-free for over six months, including the past week where it has been 85 degrees, with nearly 100% humidity. Plus this fix is free.

Go to:
http://www.automotiveforums.com/vbulletin/showthread.php?t=324015


I cleaned it a couple of weeks ago and it now seems to work fine.

billeatsrat
07-20-2005, 02:22 PM
You need to be mechanically inclined, have a steady hand, and some patience to fix the problem. The problem is a bad connection on the temperature control between a springy copper metal contact and the carbon plating on the printed circuit board.

You need to remove the black plastic cover around the key hole. With some pushing and pulling you should be able to pop out the grey plastic cover that goes over the radio and AC controls. I cannot remember if the screw at the bottom left of the panel has to be removed in order to completely remove the plastic cover. You may need to start the car to move the gear shifter out of the way so that the gray plastic cover is out of your way.

With the ignition off and the keys out:
Remove the three AC control knobs. A small flat blade screwdriver to pry under the knobs might help if they seem stuck. Carefully.

Remove the two outer screws that secures the AC switch panel to the dash.
Very carefully pry the front and back covers apart and be careful not to lose any of the plastic pieces that fall out. If you are really careful none of the plastic buttons will fall out of place.
Once the front and rear halves are separated you should be able to see the copper fingers on the center control and the carbon plating on the printed circuit board.
Carefully bend the copper fingers outward just a little using your finger. Take a very clean white towel and wipe down the carbon plating. Use a little bit of water on the rag if the carbon plating is visibly dirty. WARNING: Do not use any solvent, anything abrasive, or switch cleaner on the plating and do not rub hard when cleaning the surface.

Carefully reassemble the control panel and the reinstall. It usually lasts me about a year or so before the problem reoccurs. I have a 98 Malibu and I have been doing this same procedure for the last 4 years.

It is a very bad design flaw and I am sure that GM service centers are making a bundle on this one.

Hope this helps.

Bill

MyBluMalibu
08-13-2005, 11:16 PM
This is a normal problem with '97-'99 (and possibly later) Malibus. The problem is NOT in the A/C unit. It's what GM calls the "control module". Basically a cheap dash part. Mine has been replaced three times, on my '98 LS, all under GMPP, so have no idea about the cost. The A/C is fine; it's the dash unit. GM is known for excellent A/C. If only the dash switch cooperated.....
Yes, I am having the same issue on my 98 as far as the 1 and 2 not working could you help me on why it does not blow? Only 3-5 work? I have also posted my other issues on here as well that maybe or maybe not you can help? Thanks so much!!! Carla (MyBluMalibu)

micosan
06-11-2007, 11:38 AM
just wondering if any body knows were the control module is and how hard it is to replace it. any help would be greatly app.

http://www.aircondition.com/tech/getattachment.php?data=NDB8QUNfQ29udHJvbGxlcnNBcmV SZXBhaXJhYmxlLnBkZg%3D%3D

BeatnikTermite
06-20-2007, 09:16 AM
You need to be mechanically inclined, have a steady hand, and some patience to fix the problem. The problem is a bad connection on the temperature control between a springy copper metal contact and the carbon plating on the printed circuit board.

You need to remove the black plastic cover around the key hole. With some pushing and pulling you should be able to pop out the grey plastic cover that goes over the radio and AC controls. I cannot remember if the screw at the bottom left of the panel has to be removed in order to completely remove the plastic cover. You may need to start the car to move the gear shifter out of the way so that the gray plastic cover is out of your way.

With the ignition off and the keys out:
Remove the three AC control knobs. A small flat blade screwdriver to pry under the knobs might help if they seem stuck. Carefully.

Remove the two outer screws that secures the AC switch panel to the dash.
Very carefully pry the front and back covers apart and be careful not to lose any of the plastic pieces that fall out. If you are really careful none of the plastic buttons will fall out of place.
Once the front and rear halves are separated you should be able to see the copper fingers on the center control and the carbon plating on the printed circuit board.
Carefully bend the copper fingers outward just a little using your finger. Take a very clean white towel and wipe down the carbon plating. Use a little bit of water on the rag if the carbon plating is visibly dirty. WARNING: Do not use any solvent, anything abrasive, or switch cleaner on the plating and do not rub hard when cleaning the surface.

Carefully reassemble the control panel and the reinstall. It usually lasts me about a year or so before the problem reoccurs. I have a 98 Malibu and I have been doing this same procedure for the last 4 years.

It is a very bad design flaw and I am sure that GM service centers are making a bundle on this one.

Hope this helps.

Bill


All of this is addressed in the link I posted at the top of the page, and is the same in the link above by micosan, but those include pictures.

Also, I would not recommend cleaning electric components with water, ever.

Philoushka
06-21-2007, 09:44 PM
This fix worked for me. No more mysterious auto-off-AC. Thanks to OP.

Speedy_1234
06-25-2007, 07:51 AM
Well, My started to no cool they insterted the computer the fan clutch would not go in the car had freon the controls were fine the Special Fuse it use was ok the relay was ok But the Mech told me it might be the coil So I change the coil and what do you know the ac was working agian with out changing the ac compersor and with out taking it apart which save me in the freon stuff.

usmailman956
07-09-2007, 08:09 PM
The control head(the dash unit) is the problem there is a post somewhere that details the procedure for fixing the control head or it can be replaced it just snaps into dash and then wired up. Had mine replaced 2 times under warranty on my 03 ls. This is a common problem with malibus

wade623
08-05-2007, 02:30 AM
mine had the same problem so i took it out and cleadit and put it back together but now the control for where the fan blows does not seem to work it only blows ont the head and feet setting does anybody kno y

horndawg54
08-11-2007, 06:26 PM
just wondering if any body knows were the control module is and how hard it is to replace it. any help would be greatly app.

The control module is the part with the blower switch, temp control, air direction know. it also has the rear defrost button and AC button.

easy to relplace. pull the plastic bezel surrounding the radio, and AC. 2 screws let it come out, and their are four harness connectors on the back.

I then took my unit apart piece by piece. Cleaned each moving part, knob and contact with spray contact cleaner. The I noticed these little copper connectors on the left and right knob that need to come in contact with the computer board. Since I had notice that pulling on the fan switch fixed my AC, I realized that by pulling gently on these copper connectors, would make a better connection just like I had been doing on the blower knob.

See the response in this thread that show detail web site on how to remove and clean the control uit.

horndawg54
08-11-2007, 06:28 PM
Sounds like a recall dont you think? My '98 is doing it too and it was replaced in 01. That one too does the blinky blinky on off.

LAW SUIT!!!!!

It seems almost universal, along with the faulty gas gauge problem, and yes they should recall, bu it is not a safety issue.

dsmSpidey
08-13-2007, 01:20 PM
Does anybody think this could also cause the AC fuse to blow? The 10A one in the under-hood fuse box.

theosdad
09-02-2007, 11:15 PM
You need to clean the control head. To do this remove the Dash trim and control head. You do not need to remove the vacuum hoses. Carefully open the cotrol head. You should then see the circuit board. Under where the fan and blen output knobs are there will be a metal pad. Clean this with a pencil eraser. Reassemble and all should be well. I did this on my 1999 Malibu and it worked great.

moon03
09-24-2007, 09:31 PM
I just bought a 2000 Malibu and was told the a/c didn't work so when I got it home I tried it and wow cold air. now it is doing exactally as described in several posts here. I play with the switches and buttons and sometimes it comes back. I was ready to get a used replacement but came here and found this thread, I am not afraid to look past the first page of posts for similar problems. I will get around to cleaning the contacts soon and have a printed copy of the instructions. (wish I was near the author's shop)

PTG1212
09-28-2007, 04:13 PM
It's actually a pretty easy fix. I did it about 4-5 weeks ago and it's been working great.

I used a pencil eraser, then a cotton swab with alcohol then put some graphite, using a pencil, on the contact pads. The only problem I had is that one of the plastic stubs that holds the fastener for the fascia piece broke. I glued it and it seems to have held. Not a big deal. Everything is held tight.

Whole process took no longer than 20 minutes. Pop the little piece off around the ignition key first. The fasteners for the larger fascia piece that covers the whole center area are as follows. Two near the ignition key area, one upper RHS, one lower LHS and RHS.

The circuit board is held in by two small clips at the top and bottom of the board. Press these in and the board comes right out.

You don't have to remove the vacuum and other connectors. The fix can be done while it's connected.

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