I had the same situation with my 2004 C5. Things were working, but no display. Decided "WTF"...bought the "cool solder" tool and gave it a try. By the time I was done, I didn't know if I had done any good...but...plugged everything back in and it has worked perfectly ever since! Good Luck!

 

Thanks for the reply. I think this will be my project for next weekend. Hopefully I don't jack it up and lose my AC. I will update once I do it.

 

I performed this job a few years ago and over time the display became totally dark. Recently, since I had the console taken apart, I decided to fix the display problem. After removing the control unit, I removed the circuit board and discovered one of the surface mount resistors had fallen off and was nowhere to be found. That probably explains why the display isn't even dim now, it's blank!

I did some research and here's the data on the part: It's called a surface mount resistor and the 241 that's stamped on the top is a code signifying the value of the resistor in ohms. The first 2 digits are the basic ohm value and the 3rd digit is the number of zeroes to be added to the first 2 digits. Consequently, 241 means the resistor is 240 ohms. I found an on-line electronics supplier that probably deals primarily with corporate users, but the company provided outstanding service to me, a residential customer. Just so I'd have plenty extra in case this happens again, I ordered 10 of these things on Tuesday afternoon and they arrived today (Thursday). That's pretty snappy considering they came all the way from Minnesota (I'm in Vegas). The part # is P240WDKR-ND made by Panasonic Electronic Components.

I've already soldered one of the new units to the circuit board, re-installed the control unit, and my display is back.

 

Can someone recommend a soldering iron for this task, preferably cheap and available on Amazon (Prime)? I have an iron, but it's probably 20 years old now, so I think I'd like to use something new for this. Any particular tip and/or solder recommended?

 

Something like this would work fine if you're just going to use it for the display. If you want a quality iron to use for multiple projects, you can't go wrong with one of these.

 

I just did mine this evening. Finally can see the display what a difference.

I am no solder expert, but when I started the 241 thingy fell out of place a couple of time No solder from the factory on some. Anyway, Mine is not perfect but it works. And it was easy to remove the console.

The way I solder it was just melting a small amount on the board, then just move it around to the other locations. There were some extra solder that came off from what I was doing because to was too much, anyway remelted the solder on the board and moved it around some. It does not take a lot of solder.

 

Isn't it magical when you put it back together and it all lights up?

 

PLEASE show me a pic of the back of the A/C control with the plug in correct position..Please!

 

I am sorry don't have a photo but, every thing should line up correctly.

I actually had burned a lil on the plastic white piece where you make the connection back to the A/C unit, bbut it went in correctly. Don't force it.

 

Thanks, this worked great on my '02!

 

Kudos to the forum group for this, watched my display get dimmer over the last several months and fixed it today, nice to see a bright display again! Best part was I already had what I needed, so 0 time and $0 spent, and didn't take long at all.

 

Well after dim or black display randomly the past few months...finally broke down to do this. I was going to try the soldering myself since I have a nice solder tool I have never used... and some rosin core solder I got for something else. Mentioned it to guy that works for me and he is hobbyist robotic inventor and more....so he said if I got it out he would do it for me as he had low heat and much finer solder as my stuff was pretty thick.

Pulled apart console...removed HVAC...removed screws so he could see exactly what needed solder re-flowed and touched up. He knocked it out in couple minutes.... Reinstalled HVAC and buttoned up console and dash.

Display is brighter than it has ever been....amazing. This forum has already paid for any money I have spent and will in future. Sharing these tricks and tips is mandatory for a happy and satisfied owner of aging cars no matter if performance or luxury based.

Now to source my own solder that is a smaller diameter so wont have to wait on someone else next time something needs it...

I have the Weller WES51 electronic soldering tool... need to pick up a smaller tip as well I think.

Thanks again to everyone that figures out solutions and then captures them for the rest of us to try ourselves.

 

So I've never really soldered and didn't exactly know what to solder so I went a little crazy and did everything... now I'm concerned I ruined the board with the black smudge in pic 3. I can't test it because the car is apart for the next month is while other work is being done. Think this will work, or if not can I fix it. If you guys say it looks bad I'll buy a new one....

 

Holy cow you made a mess of that!

You only needed to solder the little black 241 resistors in the last pic!

I think your soldering iron may have been too hot! And you used way too much solder.

 

Hum so what should I do?

 

Honestly, IMO you should just head to eBay or one of the Vette recyclers here and buy a new unit.

 

Jesus.....Christ.....

Please put down the soldering iron, put your hands on your head, and get on your knees. Your crimes against electronics are too great.

 

First thing to do... take the whole board to an electronics shop, let them clean up the mess and re-solder as needed. You always use a fine tip soldering iron for this sort of close up, tiny stuff, (15w to 30ish) and not a big ol' 150w Weller gun. If nothing is damaged, spend $5-10 bux at an electronic shop and they should be able to undo this, clean it up and do it correctly. I will give you an E for effort and a monstrously gigantic B for BIG BRASS ONES. I do like your can-do attitude but we need a gentler hand on this one.. Please purchase a smaller soldering iron (many places have them), some fine solder (its a little bigger than a large cotton thread - don't use the big ol' 1/8" solder... thats for really heavy duty soldering) and then get some practice in on some old boards. Hosing your HVAC head unit is not worth it. Again, kudos for the brave attempt.

 

I got a butane Dremel with changeable tips. I used the finest one and heated the solder and used a scraper to get the excess off. Then cleaned up all the big ugly spots. After that I used clectronics cleaner and sprayed the whole thing down and got off all the burn spots and slag. It dosnt look like anything is touching anything it shouldn't be. I am going to see if it works when I get the car back together. If not I'll take it to a shop. If that fails I'll buy a new one...

Will a small bit of slag on top of the resistors affect anything if they arnt bridging the 2 sides? A couple spots I couldn't clean up well

 

Technically, no, the solder sitting on the side of a resistor shouldn't change its resistance, but you may have burned up the resistor in the process.

Get a solder sucker and fix it properly.