How to Ground Brake Assembly Magnet on Older Camper

Question:

Which is the ideal way to ground my new dexter electric brakes? A ground wire all the way to the white wire on the trailer connector then from the white wire on the truck connector all the way to the battery negative terminal, or to the trailer frame as close to the axle as possible, or to the backing plate? No place to attach ground to the old solid Hadco axle. I have read here to ground them as close to the magnets as possible. My concern is with our 1962 Shasta trailer there is a fair amount of corrosion on the frame. These brakes are replacing the original Kelsey/Hayes round magnet style brakes that work well until recently when the magnets wore out. I have every thing hooked up and brakes adjusted but brakes do not work, all lights work. Used the original ground wires to run back to a good ground screwed into the front frame rail on the trailer. I run new power wire and teed it to each brake so they would be wired parallel, before they were wired in seriesboth wires to one side then to the other. Getting just over 10v at the truck plug at full power. When I pin the bluebrake power wire on the trailer side I get power when the grounds are NOT hooked up, but no power when they are. Thanks, Ted N.

asked by: Ted N

Expert Reply:

I'd ground the magnet to the trailer frame as close as possible to the magnet, but also run a ground wire from that screw to the main ground on the trailer tongue. Where the ring terminals ground to the trailer frame, make sure that there's a dime sized spot of bare metal around the hole, and use a star washer between the ring terminal and the trailer frame to bite into the metal for a good connection. Once installed, hit the ground screw with a quick splort of rust resistant spray paint like Rust-Oleum. This way, you have all your bases covered.

I'd also recommend giving that frame a good looking over. If it's structural integrity is compromised to the point where maintaining a continuous ground through the frame isn't possible, I'd be concerned.

I'll link you to our trailer wiring help article, which you might find useful.

expert reply by: Mike L