Write-Up: Fixing HVAC Climate Control Lighting

I may have messed something up with my original unit. The display is a little funky. when the unit is off, Auto and Off button LED's are both illuminated, and the display shows the exterior temperature just fine. Once I turn the unit on, no matter the mode, it tries to show exterior and interior set temperature at the SAME TIME. And, in negative degrees lol.

I swapped in my spare unit for the time being. I liked my red Off LED too

Using your photos take a second look at how you resoldered your resistors and use a meter to check for continuity between the resistors and the PC board traces. I am thinking you have a rosin bubble that is insulating a connection, one of the original resistors was marginal and the heat from resoldering did it in giving you an open or moving the resistance, or a trace is open.

When I re-did my board I used higher wattage/same value/narrower tolerance resistors meant for use in RF applications, that I bought from DigiKey (http://www.digikey.com). I also ended up wire-wrapping the connections as the heat had done in the traces on the board.

Albertj

I think you're right Albert. I've obviously already swapped the unit out so I can work on it whenever. I see what you're talking about in the pictures, looking back. Easy enough to redo! I just liked my red LED lol.

Here's my problem with my '98 Riv. A bulb's out. OK...dash fascia removed. Done. Two screws holding in the HVAC control module-removed. Everyone says remove the unit and then take a small...(fill in helpful instructions). Question. HOW DO YOU DISCONNECT THE ELECTRICAL CONNECTOR. I have a very short harness and can barely fit my hand around to the back, and with a mirror I can see wires (about 4 or 5) and two blue tabs. Yeah, actually tabs you might be able to pull straight back, but without any guidance on whether to pull the tabs, push the tabs, press up or press down, nothing appears to be coming loose. GM service manuals are of zero help. Nothing on YouTube. Since this post is old, photo bucket photos are deadlined. I can deal with the soldering, etc. I first have to GET IT OUT OF THE CAR first without screwing things up any further. I pulled the radio down to perhaps gain me a little additional wiggle room. Good for GM to save 12¢ per unit by not adding 4 more inches of wire where you can actually look at the back and actually figure this out. Any help, naturally, would be appreciated.

DISREGARD LAST POST. MR. NUMBNUTS just figured it out. I was able to see it and it simply pulled straight out. I'm TOTALLY embarrassed, but at least I didn't break anything. I see this unit was on a 95-99 LeSabre, a 95-96 Park Avenue, and a 96-99 Riv, or so said a posting on eBay where someone will refurbish your unit for 80 bucks.

EyeDoc1 wrote:

DISREGARD LAST POST.  MR. NUMBNUTS just figured it out.  I was able to see it and it simply pulled straight out.  I'm TOTALLY embarrassed, but at least I didn't break anything.  I see this unit was on a 95-99 LeSabre, a 95-96 Park Avenue, and a 96-99 Riv, or so said a posting on eBay where someone will refurbish your unit for 80 bucks.

...it's OK, all of us who've worked on the HVAC control unit bulbs had to do one thing or another to figure out how to get the connector off.

Albertj