Poss alternator/volt guage problem

[xrayman]

Hello Everyone,
The alt guage in my truck reads well over 19 volts at times. I have had the alt tested at places like auto zone and it tests fine 12,13 volts. The guage does not go all the way back to the left when the truck is turned off when this happens, which makes me think its the guage. When the truck is turned the guage does move so it is getting electricty Any one expierence this? Thanks for any responses?

 

[Rivieraracing]

Use a voltmeter on the battery while the truck is running to confirm if it's actually 19 volts, that would answer your question if it's the alternator or not!

 

[pfowler]

I'd pull the gauge cluster out and zero out the needle. Probably take less than a half hour including the required beer break.

---------- Post added at 03:43 PM ---------- Previous post was at 03:34 PM ----------

Just re-read OP... Sorry, still hungover. Check the connection of the signal wire to the gauge from the alternator, and if you have an FVD (foreign voltage detector) I'd get that out and aim it at the connection on the alternator. If you've got a bad/ exposed wire and it's picking up static voltage from the alternator belt & pulley, that would cause your symptoms also.