crazyro wrote:
Lynnmor wrote:
When you pulled the breakaway switch, you should have jacked up at least one wheel to test if the brakes work. Often there will be no sound to indicate the brakes work. After testing this way, and there is no braking, you can rule out the truck. It is a simple system using wires and magnets, no special skills are needed.
I was hoping to hear it hum/buzz but nothing. Will jack camper up and remove at least one wheel and see if the pads move/magnets engage. I'll need to check and possibly pack bearings anyway, so this step will happen at some point or another. :)
hum/buzz is an Internet myth/fantasy which the supply is a straight unmodulated DC (Direct Current) like direct from the 12V battery and your breakaway switch.
If you have a compass you can use that to see if you have any deflection/direction change near the drum.. BUT that method is not 100% accurate or reliable since a lot of the magnetic field generated gets dissipated randomly around the entire drum..
As mentioned, lift one wheel, pull breakaway pin and see if you can turn the wheel. Wheel should turn SLIGHTLY and then stop.. You should not be able to move the wheel by hand once it locks..
If it does not lockup or just drags and turns by hand then you need to verify that the magnets are getting FULL 12V from the battery and breakaway switch.
Repeat the process on all wheels one at a time.
If each wheel locks up with the breakaway pin removed then you need to start looking at the vehicle wiring/controller.
If each wheel does not lockup then issue is on the trailer side and now you have to narrow it down to wiring or mechanical on the trailer.
That means pulling each drum and inspecting the magnet wires and mechanicals. With wheel off it is also far easier to inspect the magnet wire connection on the axle tubes.. Those connections the manufacturers do not typically use weather proof splices and the connection corrodes which increases electrical resistance that reduces the magnet strength.
Manufacturers also use too light of a ga of wire for the length of the run which also reduces the voltage the magnets will get which decreases the current draw and strength of the magnets.. Replacing factory wire and upsizing the wire size can improve braking power.
Now for the "hum/buzz", you MIGHT be able to hear a slight hmm or buzz IF you are operating the BRAKE CONTROLLER and that is due to the brake controller using PWM (pulse width modulation).. But on modern day brake controllers that is nearly impossible to do.
Most modern day aftermarket brake controllers and built in IBC controllers will limit the output to 25% OR LESS while you are sitting still making this method of troubleshooting near impossible to do.. I would highly recommend you read the brake controller's manual to get a full understanding on what it does while in a stopped position..
