[rohrmann]

If pulling the plunger on the breakaway switch does not set the brakes, you have a wiring issue, you don't have the battery hooked up, or may have a bad breakaway switch. A wiring problem would also affect braking when hooked up to the truck. Hopefully the controller works, but the brakes not working with the breakaway switch should be the first thing to fix before you tow the rig.