Why does my Chevy Blazer voltage gauge fluctuate so much?

Answer by  4by4 (36)

Voltage gauge fluctuation can be due to alternator or battery problems,a bad voltage regulator, or a bad ground. Generally alternator or battery problems will just make the voltage reading go down, but it won't fluctuate. A bad ground is the culprit to most electrical charging issues in a vehicle. A mechanic could find the exact problem easily.

Answer by  Jsands1982 (871)

Check your connection from the dash to your other components. There might be a wire grounding out or a cross connection. Please make sure you disconnect the battery if you were to do this work. Also Online websites have diagrams and tear down and rebuilt manuals will have these diagrams.

Answer by  Jimbob (2275)

When you are at higher speeds the engine is turning the alternator at a higher pace and this makes the gauge move.

Answer by  harper2583 (466)

Your voltage guage is probley moving for one of the next 2 reasons. Reason one is that your batterie is bad, and reason number 2 is that your altinator could be bad.