Hey, I am new here and i just had a question. I recently bought my second blazer (99 4 door 4.3L 4x4 LT) and its speedometer jumps up as you speed up, at about 20mph intervals. Also the temp gauge always stays at the lowest and the fuel gauge stays at empty. I have an autotap so i hooked it up and all the sensors are working like they should. I can see the speed go up normally and the temp is where it should be along with the fuel level being at full, I just filled it. I was going to take the cluster out tomorrow and see if there was anything visible and clean up the connector. I was planning on just replacing the whole thing but was just looking to see if anyone had any input. Also the rest of the gauge works fine, tach, odometer, voltage, and oil pressure.

 

Take a look at the solder joints on the back of the cluster. At this point, it sounds as though the cluster is the issue.

Where in NY are you from?

 

Dutchess County, Pawling, NY to be specific.

 

check the # 4 fuse in the fuse box. if this fuse blows none of the gauges will work. the fuse is for the gague cluster.

 

Ok so i bought a used cluster... and the only thing that started working was the speedometer. I then went and pulled every fuse in the car and flipped it to find that not much happened. I then looked at the #3 and #4 fuse and flipped them around and all the sudden i got the fuel gauge to work and temperature gauge. But now i have a new problem. And i know ive read about this but couldn't find it. The PRND321 and odometer don't light up after thee first click. i checked out the entire thing and found no broken connections. However the old one this works great, so i know it has nothing to do with the ignition. Honestly i can live without it because i now have a fuel gauge... but any input would help. Also im going and buying a ton of good fuses and replacing every one because thats the reason that all this happened because they were corroded.

 

So for the past two hours in and out of the dark i went and resoldered all the connectors that others said were bad, pin one on the odometer and gear select. one was alittle cracked but was still connected. However this didnt do anything. I realized that when i unhooked the #3 fuse before i never looked to see what it was. So in my last attempt of the night i realized that it was cruse control. And i sat for a second and went what the hell and unplugged it and all the sudden the Gear select lit up and the odometer lit up.... i cannot dim them but the rest of the dash dims. but it is working. I think there is a short in the cruse control somewhere because that is what was making the Temperature, and fuel gauges not work. I have to dig deeper into this but for now i could care less about the cruse control. Now, if anyone knows does that fuse do anything besides cruse control?

 

I know this is a old thread however you are the only person to get this far on this Known issue with the chevrolet instrument cluster, which I myself have not been able to fix. This is a last ditch effort before not becoming a chevrolet owner anymore, don't get me wrong i love my truck and have dump several thousand in customizing it to make me happy with it but too many problems and it is problematic. I cant private message you but please if you can conclude your finding about how you fixed this issue it would be grateful everyone is wrong that i have talked to and you are the only person that has got the gauges working properly.

 

Well the way I fixed this was I replaced the instrument cluster pulled the cruse control fuse, and dealt without the crusie control. It seemed like it started to work when I kind of pulled the fuse and put it back in again a couple of times and it only worked after i replaced the cluster. But for it to work constantly i had to remove the fuse. Actually the cluster was slightly different then the original, that is i think it was from a 98 and my truck was a 99, it did everything the same but the actual board was slightly different. Not sure if that mattered. I had them both stripped apart thinking it was something wrong with the cluster themselves. But once i played with the cruise control fuse the thing started working again, but if i put it back in it stopped working.

The funny thing is that i actually sold this truck(the 99) about a month and a half ago after i put a bunch of money into it. It just had too many problems. I have a 97 which was before all the changes and that one has more miles on it and no problems. I will never buy a 98 or newer blazer again. I also realize that that fix sounds stupid but it worked and didn't stop working once i "fixed" it. If you have any other questions just ask and ill try to help.

 

i have a 99 blazer the speedometer, rpm, and tempature guages are not working and the fuel gauge is stuck at full when i know there is only a quater tank. i have checked the cluster it looks fine i pulled the cruise but got nothing swiched around the 3rd and 4th fuse's and got nothing and km and gear slecter lights are not working