look for something, like this, along the A-frame of the trailer:
usually tucked inside where you can't see it.
press the black button on the side.
Dan- Firefighter, Retired:C, Shawn- Musician/Entrepreneur:W, Zoe- Faithful Golden Retriever(RIP:(), 2014 Ford F150 3.5 EcoboostMax Tow pkg, 2016 PrimeTime TracerAIR 255 w/4pt Equalizer and 5 Mtn. bikes and 2 Road bikes