My friend's 92 Corvette is having a problem with his climate control buttons. Sometimes the buttons stick and he can't turn the AC off or adjust the temperature, so he winds up playing piano until they start working again. Any suggestions?

 

Yep... Common problem. He needs to take the Climate Control (CC) unit out and clean the circuit board. Before you (or he) get scared at the sound of this, let me just tell you that it is EASY.

Start by removing the lid to the center console (4 bolts). Next, lift up the carpet liner inside. At the rear of the shifter trim plate, there will be 2 bolts that hold the back down. A third is under the cupholder/ashtray linter. With those three out, the shifter trim plate should easily lift up and away. Just position it to the side and remove the two (identical to the previous 3) bolts at the bottom of the radio/CC trim plate. Next, remove the central A/C vent (2 Torx screws). When that's done, you'll see a third Torx screw that's holding the top of the radio/CC trim piece in that needs to be revomed. After that trim piece is off, you'll notice the two bolts holding the CC unit in place - remove them. The unit will now slide straight out, and you can unplug it from the wiring harness in the rear.

Take the CC unit inside to work on it. There will be 6 *small* bolts that need to come out - 4mm or 4.5mm, if I remember correctly. One tip I can give you is this - when you've got all 6 removed (two on the back surface, and 4 around the perimeter), point the face of the CC unit towards the ground while separating the two halves - you don't want the individual buttons to fall all over the place. With that complete, you will be able to remove the internals. There will be 2 circuit boards joined like a "T". They simply pull apart. Set the larger of the two aside. Then CAREFULLY remove the 4 lightbulbs (will look like grey plastic plugs from the back) with a flathead screwdriver - they should take about a 1/4 turn counterclockwise to "unlock." After they're out, flip the board over and proceed with the cleaning.

All I do is *lightly* go over the contact points (you'll be able to tell what I'm talking about when you have it apart) with a soft pencil eraser, and then give it a good wipe with some Isopropyl Alcohol pads. After it's dry, I re-assemble and head back to the car. Plug it in to the wiring harness for a test - it should work as new!

Re-assemble all other trim pieces, etc. in the order they were removed. Shouldn't take more than an hour...maybe a tick more depending on how careful you are. It really *IS* an easy job, though, so take your time and all will be fine.

Hope this helps! I've done it twice on my 96 with no problems (most recently over this past weekend). It sure beats a new unit at dealer prices (around $375, I think)!!!!!

 

I replaced mine for just over $100....I'm lazy

 

Thanks alot. You are the best!

 

Removing the center consel is a little tricky but your right this was easy... and worked well.

Nice advice.

 

Trueblue92 and WayneGro,

Thanks! Glad to be of service... Fixing something yourself on your Corvette is really one of the best feelings. Whenever there's an opportunity to "show someone the way" to solving a problem for free that would otherwise cost them several hundred dollars, I jump at it.

Now just remember what you did and how you did it! In a year or two, the buttons may start doing the same thing again. Just clean it again, and all will be well.

 

Thanks for the hint -- worked on my 93 with the electronic climate control as well -- but there were a couple minor differences to watch out for -- I don't know if it is 93 vs. 92 or just some mid-year change in the components:

1. The screws for the a/c vent were Phillips head, not Torx.

2. To remove the circuit boards after separating the 2 halves of the box there are two more 4mm bolts that attach the smaller cicuit board to the front (button side) of the box. The board did not simply come out of the box when I opened it up but the bolts were pretty obvious and removing them did the trick.

One "funny" part of this exercise (I am not very mechanical). When I reassembled the circuitboards, I was off by one pin (those who have done this will know what I mean). So, when I reinstalled and tested the unit, the buttons produced random results. What's worse, the select ride warning light went on! Naturally, I thought I'd made matters worse as I often do trying to save a few bucks by doing my own maintenance. You can imagine my relief when I opened the box up again and found my boneheaded move. Everything works perfectly now.

 

Many, many thanks!! (I'll give it a go this w/e!!)

P.

 

On the preventive maintenance tip, Radio Shack sells a cleaner/degreaser for electronics in a spray can that works great on HVAC panels, too.

 

The tetrachloroethylene type was used as dry cleaning fluid at one time (works good to remove grease spots from silk ties, I can tell ya!), It leaves no residue and will "blast" particles away in a second! It comes by many names for various purposes, including electronics parts cleaning. Most any auto parts store will have it on hand. (Be sure it is the tetrachloral type tho...)

FWIW,

P.

 

Good info!