Break Away Kit
You are on course to install a proportional brake controller, such as Tekonsha Prodigy 2 (or 3) or similar. This applies the electric actuated trailer brakes when the TV brakes are applied, in proportion to the deceleration of the TV.
A necessary part of the system is a kill switch (sometimes called a "break away kit") which will apply full trailer brakes in the unlikely event your hitch fails and the trailer becomes disconnected from the TV. On my '07 Bambi, this switch came from the factory as standard equipment. It is a switch (in a little box on near the tongue) which is hard-wired between the battery and the brakes. A plastic "pin" is inserted in the box to keep the switch normally open (no brakes applied). A safety wire (non-electrical) is looped through the hitch receiver on the TV. If the trailer departs the TV, this safety cable yanks the pin out of the switch, and the brakes are applied.
Part of the hitch / unhitch ritual is to attach / remove this safety cable and pin. The pin is never deliberately removed from the switch for more than a brief moment, so as not to burn out the brake actuators.
Hope this helps...