Quick question...When I come to a light, I can see the voltage gauge in the dash dip below 10 and the dash lights get dim. It's a digital dash btw. As soon I get going, voltage goes back to normal. Had autozone check both battery and alternator, and both tests came back fine. They checked them both while truck was running. Any ideas? Thanks in advance..

 

How low did your RPMs dip when you came to a stop? It is possible that the power usage was higher than the alternator could support at the given engine RPM.

 

not much really...nothing on except for radio..happens during the day and at night..

 

anyone?