2016 Peterbuilt 579 voltage drops then jumps back up. just started the other day thought it was an alternator but swapped that out and still having problems, alternator reads 14v as well as the batteries, but the truck dash never goes above 13.3v then slowly drops to 8v then jumps back to 12 or 13 then the cycle repeats.
2016 Peterbuilt 579 voltage drops then jumps back up
Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by jiwion82, Dec 3, 2023.