Trailer brakes

Charlie D. wrote:
There is a label on my pin box stating that a minimum 12 A/H WET CELL battery must be installed to activate the brakes if a disconnect should occur. That stood out to me because I have read on this and other forums that some people are using glass mat batteries. Something to check.

12 volts is 12 volts are glass mat volts different than wet cell?

There is a label on my pin box stating that a minimum 12 A/H WET CELL battery must be installed to activate the brakes if a disconnect should occur. That stood out to me because I have read on this and other forums that some people are using glass mat batteries. Something to check.

I think if you look closely at your wiring at the kingpin j- box ,the black charge wire that runs from the truck to the fifth battery to charge it has the breakaway wire on the camper side of a fuse , so if the fuse blows or the camper disconnects the breakaway works on the camper battery , if the fuse is good and the truck is connected the power is shared , one charge system - truck and camper

The blue brake controller wire operates the brakes in conjunction with the truck brakes and comes directly from the truck

Trailer lights wires are from truck only
brown = running
green = right brake and turn
yellow= left brake and turn
red = backup
white = common ground

Its a law that the breakaway has a battery connected to it when the trailer is towed

If the trailer's umbilical isn't connected to the truck, the trailer brakes won't work regardless of the trailer batteries' state of charge - the trailer batteries only get involved in case the breakaway switch is triggered.

Rusty

If you have your campers electrical cable plugged into the truck the truck's electrical system will power the electric brakes. So yes your trailers brakes will work without your trailers battery being connected. However if your trailer's battery is disconnected and the trailer's electrical cable is not plugged into your truck the electric brakes will not work.

They are accurate on the brake-away brakes for trailers over the state limit.

My bad

Working trailer brakes via emergency brake switch (trailer battery) is REQUIRED by law on trailers above typically 3000# GVWR (Some state have lower/higher weight limits)

MI is 3000#

Should never tow without a working trailer battery

Battery is required for the break-away system to work.

Your TV will slowly charge the battery of its hooked up, but otherwise the battery is not needed.

Exactly. The battery is used by the brakes only if if it becomes disconnected from the TV. This via the breakaway sw. The trailer lights and the brakes work thru the truck lights and the brake controller thru the cord.