azdryheat wrote:
Breakaway uses the 5th wheel's 12v battery. To test, I jack up the trailer to get the tires off the ground. I pull the breakaway pin and then try to spin a tire. Tire should move slightly and then lockup if the breakaway is working. I put the pin back in the breakaway and the tire should move freely. I do this for all six tires.
Just as azdryheat says, I jack one wheel at a time give it a spin and pull the pin, if it stops that wheels working, next wheel same routine until all wheels have be checked. The 5W battery must be charged as it powers the brakes.