2005 Sierra 1500 Wacky Voltage Gauge

One owner 2005 Crew Cab 1500. 65,858 actual miles. VIN 2GTEK13T251106263.

Voltage gauge indicates extreme voltage readings (19v+), but checking voltage at the battery with engine off is 12.22 volts. Checking voltage at the battery with engine running is 14.28 volts.

Worried the hell out of me for a while, but I've been using the truck with absolutely no electrical problems for several months now.

Should I continue to ignore? That'd possibly bite me come sale/trade-in time.

What should I look for to remedy this problem?

Thanks,

Giff Kucsma

I would include pictures of the gauge readings but the Forum keeps telling me that .jpg and .png are not valid image formats.

I would suspect connection problems at the instrument cluster first. I believe there are two connectors at the corners of the cluster which plug in when the cluster is screwed into position.

At least you have verified that the system voltage is acceptable, and that it should be safe to drive.

Thanks for the suggestion. I hate tearing into dashboards, but I'll give it a try. Except it'll have to wait until warmer weather arrives. The Sierra won't fit in my garage.

FYI, I’ve solved my wacky voltage gauge problem. My speedometer also went wacky recently. I just finished replacing all of the stepper motors in the gauge cluster - problem solved.

At three bucks apiece it only makes sense to simply replace all of them once the cluster is on the bench.