We tried a fuse, but thats not the problem.
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1991 Chevrolet S10 Blazer Question: What would cause the digital dash to fail? Other than a fuse?
Answer #1mastertech6371 December 25, 2011, 15:22Master
the cluster itself may have failed. once you determine there is power to the cluster and the connector is ok, then the cluster is the issue.
dpasek January 29, 2012, 21:22Enthusiast
Inside the digital cluster, there is a power supply module for all of the blue vacuum fluorescent gauges (fuel, oil pressure, engine temp, voltage, and rpm.) You need an electronics guy to remove the rear circuit board to get to the small power supply circuit board that is attached to it. Replace the 43uF electrolytic capacitor (a 50 cent part) and that may fix the problem. Another possibility is the two 2SC3328 transistors (about $1 ea.) More details here: http://chevroletforum.com/forum/s-10-blazer-20/92s-10-bla...
The instrument cluster is a bit of a nuisance to remove, but there are instructions elsewhere on the web. The hardest part is removing the climate control cluster on the right hand side so that the instrument cluster escutcheon can be pulled out.
While you have the cluster out, replace the two PC194 lamps that light the PRNOD21 indicator and the tach yellow and redline markers. No need to replace the others.