The ''Help! Low Blower speeds don't work!'' post - Maintenance and Repair Forum
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This common problem is related to 3rd generation J-bodies. It is not unheard of for this to happen several times during the lifetime of your car.
Typically, speeds 1 and 2 (the two lowest speeds) of your HVAC blower fan stop working. Speeds 3 and 4 would continue to work.
Replace the Blower Resistor
(GM part #52476725).
(click on thumbnail to enlarge)
(reference: GM J-Platform Shop Manual)
(it is recommended that you disconnect the negative battery terminal prior to doing any work on the elecrical system of any car)
Now, in some cases, the left instrument panel insulator might be in the way. If it is, remove it before starting.
1. Locate the blower motor - you have to stick your head under the passenger side dash to see it.
2. Disconnect the electrical connections at the blower motor.
3. Remove the blower motor retaining screws.
4. Remove the blower motor and fan assembly.
5. Disconnect the electrical connection at the blower resistor.
6. Remove the blower resistor screws.
7. Remove the blower motor resistor.
1. Install the blower resistor. Tighten the screws to 1 N-m (9 lb in).
2. Connect the electrical connector at the blower resistor
3. Install the blower motor and fan assembly. Tighten the blower motor screws to 5 N-m (44 lb in).
4. Connect the blower motor electrical connector.
5. Reconnect the negative battery terminal.
What is the Blower Motor Resistor and how does it work?
The blower motor resistor is used by speeds 1 & 2 of your HVAC blower fan. It reduces the current for those speeds in order to slow down the blower fan motor. (I'm not an electrical engineer - but I think that's about as simple an explanation as you can get).
One of the screws in the back is hard to get to.
Persistance is key. I found that using a combination of a small ratchet and a small wrench got the job done. It takes a while, but it works. Some have used flexible ratchet/screwdriver extensions that can bend around to get it.
Can I just repair the damaged resistor?
Some have tried. Some have been successful. But this is not recommended. The resistor is designed to be cooled by the airflow in the duct. Modification to the resistor could result in unwanted heat - and possibly fire.
The replacement resistor is expensive! Can I get it anywhere else?
Currently there are no known aftermarket resistors that would work.
Can I make my own resistor?
Not recommended - although many have tried. It is far easier (and safer) just to fork out the cash and get the right part. <br>
I think autozone sells the resistor. <br>
Awesome post man. I just did this yesterday but quit because I couldn't get to the screw near the firewall(the back screw). Any more tips on how to get that screw out. I was cursing and getting extremely pi$$ed off.
Also, I'm getting the resistor from the chevy dealership for $16. If anyone else needs one and this is a good price, let me know. How the hell do you get that screw out, its hard enough fitting your body up in there.. Thanks.
I know it's pretty ghetto, but I ended up using the correct socket and a pair of (needle-nose vise grip) pliers to turn it. It took forever, but did work in the end. The only "correct" thing I can think of is socket universal if you can get it to fit (as stated in the top post).
If you can get your fingers by the screw, try that rubber eraser artists use. The one you can make into almost anything, i use to use it to remove oil filters and spart plugs. it might work here too. <br>
Learn before you burn
Well, for me, it was a f$%# pain in the @!#$ to get that last screw out. After two hours of cursing and bouts with claustophobia, I ended up getting it unscrewed by using a long nosed pliers.
what I did was that I "pinched" the screw really hard, kept the pliers at a 45 degree angle, and maintained that degree of angle while I twisted that damn thing. To put an analogy, kinda like those rides in an amusement park, like the swings in a merry go round style ride. They ended up swinging around, but theř're angled as they do, and they hold that angle as long as they're going round and round.
Anyway, to keep it simple, long nose pliers, pinch, hold it at 45 degree angle, and turn while maintaining the angle. Done. After that, swear some more if necessary........
I hope this helps.
you think that screw is hard to get, that is so easy compard to a heater core, to those guys that have done that, what did you think of that screw at the back. that takes skill.
blower motor is easy to remove, done it all my sunfires and think i'm pro at removing it now <br>
JBO since July 30, 2001
Well I ended up getting that damn screw out. I used a weird tool I found laying around my dads shop. Feels great now and the ac blows so hard.
I just finished replacing mine. To get the back screw I final used a dremel to remove most of the bottom of the old part so that I could get at it with vice grips and twist it out.
It was late. I was was frustrated. I had a power tool. I know a bad combination.
Looking back I realize I also forgot to put that second screw back in. Is that going to cause a problem?
I have a 1/4" flex shaft nut driver. It looks like a 6" piece of speedometer cable with 1/4 drive on one end and a handle on the other. No idea where or when i got it. It works great getting into those hard to reach places.
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"Oh! My My!" Splat . . . "Damn Squirrel ! ! !"
i got mine for 28 bucks from the dealer
nice write up ken, im tired of seeing posts about that! <br>
I used a johnson bar, and alot of swearing and tool throwing to get the last screw out. It worked pretty well. There was alot of blood.
Thank God I still had some warranty left and I just got mine fixed for free!!!
Leafs in 2004...You better believe it!!...Ok believe next year then!!
just being proactive so that i can plan ahead and maybe get a flexible socket shaft and ensure i have the right size.....what size is the the head on that last bolt? <br>
<a href="http://groups.msn.com/2000Cavalier/2002z24.msnw" target="_blank">2002 Z24</a>
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Kudos to ya! Settings 1, 2, and 3 went out on me the other week. I was wondering if it was the HVAC control panel (easy fix), or the motor and it's maybe-self contiained resistors. Now I know what I'm in for. I may live with it for a while, only use #4/high mostly in the summer for A/C anyway.
My blower resister went out, I read this post, went to Sears, bought a $9 flexible 1/4" drive screwdriver style driver, installed the new resistor in 15 minutes! Way to go J-Body people, you guys (and gals) have been a huge help!
Wow, certainly NO exageration by anyone here. That last screw by the firewall? DANG hard!!!!! I'd've loved to be able to get that rubber insulator mat thing outa the way. I wound up using a socket on the screw, u-joint on the socket, short extension on the u-joint, small socket wrench on the extension. When you think about it, not all that surprising really. Typical GM engineering for ya. Old resistor wasn't an exact matchto the new one, but was kinda close. Let's hope that they improved the design and durability of the newer part.
I just did this the other day. Yes, this was a pain in the rear end at first, but when you have the correct size socket, Holy Crap, what a difference.
I used a flex extension with the socket on the end, once I figured out the correct size, I had no problems. At first I thought it was a 6mm socket, cause that is what I used to remove the blower motor and the first screw. I was able to use the 6mm to some degree on the last screw, but then I realized it was a 7/32nd socket. I had to run to the store and get it as I did not have one. Once I got it, the job took no more then 10 minutes to fix. And to boot, I called my Chevy dealer to see how much this would cost to fix and they said $70.00.
All told I spent 33.00 +/- some change and did it myself. Saved 37.00 and gained some more knowledge.
Just to let everyone know who has not done this yet, it was not hard, just take your time and watch what you are doing.
If you're more than 4 feet tall spend the 3 min it takes to undo the 4 seat bolts and take the front passenger seat out. While its out you can retrieve your loose change as well as enjoying gobs of space to lay in to reach those tricky screws. <br>
okay now how about his - my off is off (duh) and my low and medum blower speed are the same (low) and the high is well high - whas up with that?!? where da middle??
I need to do this on my 97 RS. I was wondering what the deal was with that. Mine went out a couple of years ago. I tried to replace the switch when I had the dash apart replacing the F@$#%!G HEATER CORE. But that didnt fix it. Surely changing this should be nothing compared to that nightmare. Oh yeah... Im quite familiar with the bottom bolt against the firewall. I wanted so bad to kick the guys a** who designed that heater box. GENIUS! "Lets put a bolt on the very bottom of the heaterbox and recess it 2" and lets put it right in the center of the hump in the floor so that you cant use an extesion to get at it." The bad thing about that was you only learn of this problem after completely disassembling and removing the entire dash!. WHEW! I am glad that project is over with. But the heat is nice and toasty now! I just need to get the resistor changed out. What is it that goes bad with it? anybody know? bad solder joints or something?
Excellent post BTW, Great Site/Community. Everytime I have a problem with my car I check here first.
*** Tip for getting that front screw out ***
I pulled back the carpeting and cut a U-shaped slit in the firewall insulation (actually, and upside-down "U"). That gave me just enough room to fit a standard 1/4" socket driver on the front screw. Once the resistor module was replaced, I just put the insulation back in place.
I bought the replacement resistor module at Schuck's (Kragen, Checker) for $15.
The factory GM module is made in Mexico, but the no-name replacement I bought at Schucks was made in the USA. Go figure. Ironically, the resistor module in my wife's Oldsmobile Alero went out 3 days after the one in my Cavalier. I should get some sort of bulk discount at Schuck's ! <br>
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all of mine dont work except my last level which is full blast so should i replace the resister still? <br>
Absolutely!!!! If yours is like anyone else's, then those solder points for the lower speeds are very fouled. Not to say that they're a fire hazzard, but I don't think I'd feel safe knowing I had a screwed up electrical part under there. The newer part looked better engineered then the original.
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