I have a 2006 chevy c8500 all gagues work except speedometer and tachodmeter

If your speedometer stopped working and stays at 0 MPH, you should have your car checked ASAP. The most common causes of a speedometer that stopped working include are a faulty speed sensor, a broken gear on the speedometer, damaged wiring, or a faulty engine control unit.

Nope. The speedometer needs a signal from the vehicle speed sensor to operate. Is the check engine light on? If so, scan for any codes that may indicate a VSS problem. If no codes, possible internal cluster issue with the speedometer head

How to repair GM Instrument Cluster Speedometer Gauge Stepper

YEP YOU NEED VSS SENSOR HOOKED UP SO TRANSMISSION CAN SHIFT RIGHT.AND SHIFT TO OVER DRIVE AT SET SPEED. YES YOU NEED TO SEE YOUR SPEED TO KEEP FROM GETTING A SPEED TICKET.DONT UNPLUG IT.

2006 kia spectra speedometer not working. Try this, I just did it and it worked. Disconnect both battery cables and touch them together for about 3 seconds, then connect them back to the battery. This causes the main computer to re-load all computer programs. It worked on my kia, speedometer now working. It also worked on my 2004 Chevy Silverado to correct an AC/Heating problem just after installing a new battery. The truck blew hot and cold air at same time with only AC on.

IF it is in the radio and not a seperate computer then you do the following: Go into the vehicle settings with the radio controls. With the key turned to ACC, hold DISP on the radio for about 6 seconds and it should go into settings mode. Press DISP until you see oil life in all caps, then use Prev. & Next to scroll to reset oil life mon., then push DISP again. you should here a beep and the display should read Done. Scroll to Exit and press DISP again.

check your fues box were it say gagues

All warning lights flashing on dash of my 2002 chevy trailblazer. Runs fine all gagues go dark and turn back on every now and then. Also the gagues all go to the right or stick half way like I am idling at 5000 and going at a speed of 60mph when I am sitting still. I am thinking it has something to do with my computer because the rest of the truck is working just fine.

the problem might be in the ignition switch(not where the key goes) but what the key switch is connected to. just try this first, when the gagues stop working, hit the steering column behind the key switch and if the gagues start working then replace the ignition switch

I'm going to assume you checked the fuses, and say that the display panel will have to be replaced. On these the display is all one piece, and when one gage goes out it effects the whole thing. Some of these display panels had in line fuses on the inside circuitry, so you may be able to pull the display and change the fuse. Others were built as a sealed unit and cannot be taken apart.