If that is the original battery, it is time to replace it. Your measured voltage is low and you generally can't get dependable use out of an 8yr old battery.
The trailer is the only one with a umbilical(pigtail)cord.
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Dan-Retired California Firefighter/EMT
Shawn-Musician/Entrepreneur/Wine Expert
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing a 2014 Ford F150 SCREW XTR 4x4 3.5 Ecoboost w/Max Tow Package
4pt Equal-i-zer WDH and 1828lbs of payload capacity
Linear Mode
