Here is a good You Tube to help find where a short is coming from it will help you narrow it down...Copy and paste...https://www.youtube.com/watch?v=n5FJDgcdii8
a battery even if fully charged if it wont hold a charge / LOAD need to be replaced...if the battery load tests ok.then find whats drawing/sucking the power..any aftermarket parts?? remove 1 fuse at a time after you conneck a volt meter as shown .if its showing anything between 1-12 volts...remove one fuse at a time and see if the meter/needle..goes back to 0....of anything lower than waht you had...even if the dray shows 12 volts at the start and you pull a fuse and it now shows 10 volts ..thats part of the problem ..could have more than one...if you pull a fuse and it zeros out than thats the whole problem,that circuit..
almost guys/sound like parasitic draw most should be 5ma or less. joe mom is right it is explained well on youtube that is what i use to train my techs. you must be able to test amp draw.
Syptom of a bad battery. Have it tested.
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