Ok thanks, now I do remember years ago I used to hear them sort of clashing when I was backing in a spot and had the window open. Not sure when I last ever heard that loud clashing.
Just now, tried it while parked 7-pin connected, and son in truck, brake pedal down, beside the trailer wheels you can hear a loud humming noise, noise same from each of four wheels.
No brake pedal down, but controller slider over, same humming from each trailer wheel.
I would suspect no braking in spite of the humming (say grease on brakes or whatever) if the trailer brakes had not locked up on the breakaway braking test mentioned. Is that valid?
Mex, I don't know if it matters if the trailer brakes light up or not as such, but the controller works from the truck brake pedal switch that makes those lights work.
