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Wacky GM gauges

So, GM had some well known issues with their instrument clusters due to failing stepper motors (little electric motors that control the gauge needle movement). I’m fortunate enough to own two 2005 GM’s. I think this was right in the midst of their faulty gauge run, apparently. My 05 Sierra has a faulty voltmeter and a questionable tach. I ordered the motors months ago, but I was hesitant to replace them since it requires a bit of somewhat delicate soldering onto the circuit board, and the voltmeter and flaky tach just haven’t bothered me tremendously. Then, this week, I’m driving the 05 Lesabre. I look down at the speedometer and I’m apparently going 70 mph on a rural road. Wow, it’s a fast car! A couple of days later, I’m going 120 on the highway. Ok…that ain’t right. So I bit the bullet today and successfully replaced all 4 stepper motors in the Buick. Since a speedometer is kind of important, I figured it was worth a shot repairing them myself. $35 for stepper motors beats $200 and mailing off the gauge cluster for someone else to repair it. There are a ton of videos showing how to do the repair, and it really wasn’t that involved. Hopefully my solder joints hold up. And hopefully I can get this dash back together!

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I did the same on my gm, the motors came with replacement bulbs also. I use copper braided stuff to absorb the solder for existing motors. It soaks up the solder, and the motors then pulled right out. It is a real advantage to do the motors as a new cluster needs to be reprogrammed for $200.

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I may see if I can find that cu wick material when I do the truck’s gauges. Figure I might as well do them too at some point. I just melted the lead, then sucked it out with a shop vac! Wasn’t my original plan, but the little turkey baster bulb I tried first just didn’t have enough suck :flushed:.

This was an extremely problem for GM vehicles for quite some time

Do you have a question . . . ?

Otherwise . . . glad to hear you’ve got your vehicles repaired :+1:

John, here’s where I get desoldering braid. The prices are very high, but that’s for huge quantities. If you scroll way down the page, they have a single roll for $4.50. https://americanbeautytools.com/Desoldering-Braid/198?gclid=Cj0KCQiAl5zwBRCTARIsAIrukdNonC1oPuw8exl0O-vTH6J3kpNj7aWt-3XGEL7vGU7Jy8LgSMPE-IoaAkP8EALw_wcB

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Nah, no question.

Thanks!

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Thank you. I found some braided cu at work and experimented with it on a gauge cluster out of a scrap car, but it didn’t work very well for me. I think the cu I was using must not have been fine stranded enough, possibly. Will definitely keep this place in mind if I can’t find the cu locally.

If it is plain stuff you may need to paint on a little flux.

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This stuff has Rosin flux embedded in it. It wicks better and prevents oxidation of the desoldered joint.

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With the demise of Radio Shack, there are now very few places to buy that desoldering braid locally

Fry’s electronics used to always stock it, but they rarely have it nowadays. Fortunately, there’s a small mom and pop electronics supply store near the local Costco that seems to have all the stuff a hobbyist might need and/or want

I don’t even look for local businesses to source specialty products anymore. I get most things I need on the web without even needing to get dressed first.

I got rebuilt units for my old 04 Silverado from Summit Racing. Also, upgraded to 2500 panel so got a trans temp gauge also. Plug and play for trans temp gauge.

I’m curious what non-problem GM was trying to solve when they switched from time-tested electromagnetic and bi-metal gauges to ones with stepper motors.

Planned obsolescence comes to mind. I fear the days when circuit boards to fix a car are no longer available.

For some de-soldering jobs – even on printed wiring boards – a “solder sucker” will work better than “solder wick”.

https://www.google.com/search?q=hand+operated+desoldering+tool&rlz=1C1EODB_enUS509US509&oq=hand+operated+desoldering+tool&aqs=chrome..69i57j33.9007j0j8&sourceid=chrome&ie=UTF-8

In any case, you have to be quick with the soldering iron on the PWBs. Linger too long, and the heat will destroy the glue that holds the copeer foil to the board. (Old news, probably.)

If you have any electrical background it should be easy to see why the move to steppers makes sense from manufacturers perspective. It follows the march from analog to digital control. Direct microcontroller control of gauging means less components, less complicated parts to manufacture as a system and greater accuracy and range of motion to make it easier to build the same gauge and control elements to satisfy multiple platform requirements with just firware changes. What makes you think they didn’t sucessfully accomplish their goal?

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They simply introduced additional complexity when the existing, simpler system worked very well, with low error rates and very few failures. As for analog vs. digital, I believe that recorded music sounds a lot better on vinyl than on CD or MP3.

I think you missed the part about it being less complex in terms of component count and assembly. There are not that many failures. When they do fail, it might seem more daunting to repair if you’re not familiar with them.

From a user perspective, it’s form, fit and functional equivalent. But the reduced cost to manufacture contributes to keeping prices down in spite of all the technology and rising labor costs YoY. Nobody likes to pay more every year but imagine if they abandoned all of these kind of cost cutting CI programs…prices would be even higher…

Yeah, but carrying a record player is inconvenient. I recently decided to listen to some old albums and found my turntable wasn’t working. Bad belt. It’s linear tracking so super short belt but specific design. Found some online from Romania for big $. Hesitated and glad I did. One day playing with son and noticed a rubber band on a toy that looked familiar. Yep, exact replacement. Now I have 5…

I’ve been looking for a headshell for my Dual CS5000 for two years!