2001 F-150 won't hold charge/new battery
If the truck sits, even for a day, it won't hold a charge to start again. The
battery is new. Has a newer starter, tested the alternator- it's good. Have had
people suggest that it may be a ground, or likely something drawing when the
truck is off. It is the usual rusty '01. It was making a noise like a blinker was on
(it wasn't) after this last jump and before the charge was gone. Any ideas???
Most probably a parasitic draw. Start testing....https://www.youtube.com/watch?v=KF1gijj03_0&t=232s
As Tom said, it's a parasitic draw. They are not difficult to locate. Find video's on the net as suggested. Located the same problem on a neighbors vehicle. The switch for the glove-box light was broken and the light remained on all the time.
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