I have a 99 4x4 with a wierd problem. I have the digital dash that reads the mileage and shifter selector digitally. My problem is a month ago the odometer went crazy and read error, then 999,999 miles, then went out. The next day it reset to 0 kilometers and would count kilometers until I shut it off then it would reset at 0 again all the while still going haywire at random times. I pulled the dash and found 2 cold solder joints and resoldered them correctly. I've put 1000 kilometers on it since the fix and everything seems fine except it still reads in kilometers and doesn't have the correct mileage. I have searched the forum for answers and found a couple of threads that talk about a pcm reflash with no answer as to what fixed the problem. I just wondered if anyone else had a solution for this situation.

 

Go to the junkyard and get a new cluster from a 99 s10 or blazer and swap them. My guess is the board inside is borked. GM trucks are known to have clusters go bananas.

 

yeah that was gonna be my next move however I would like to diagnose the problem versus throw parts and money at it. Just curious if anyone had a similar problem with any concrete solutions for the issue.

 

the digital dash gets all its info from the onboard computer, if the dash itself instrument cluster that is is messed up and causing your problem the new 1 should fix it otherwise your computer is bad