voltage gauge moves with blinker
It would appear your charging system is not working properly, and the elec. drain of the lights, turn signals, and/or reverse lights is not being counteracted by the charging system suppling enough amperage to handle the drain. This could be a bad alternator, regulator, loose/worn belt, worn belt tensioner, and/or bad/poor battery. You can get a quick charging system scan at your local Auto Supply store like AutoZone etc., and that will help pinpoint where the issue(s) might be. Hope this helps!
It's normal on these trucks, just about every one I've felt with does this. Don't go waste money unless your battery light is on consistantly. The gauge sucks, it will move with the blinkers, when you turn on the lights, blower, sometimes when you just hit the brakes. It's normal
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