Installed New Trailer Brakes, Getting Power on Brake Output Circuit, But Brakes Not Functioning

Expert Reply:

I would suspect either a faulty ground connection or the brakes need adjusting. Make sure that one lead from each brake magnet is securely grounded to clean metal on the trailer frame. If the brakes themselves are actuating, but not providing stopping power, you might need to re-adjust the brakes if you have not already. The procedure for adjusting trailer brakes is as follows: Brakes should be adjusted after the first 200 miles of operation when the brake shoes and drums have “seated” and at 3000 mile intervals, or as use and performance requires. The brakes should be adjusted in the following manner: Jack up trailer and secure on adequate capacity jack stands. Follow trailer manufacturers recommendations for lifting and supporting the unit. Check that the wheel and drum rotate freely. WARNING Do not lift or support trailer on any part of the axle or the suspension system. Remove the adjusting hole cover from the adjusting slot on the bottom of the brake backing plate. With a screwdriver or standard adjusting tool, rotate the starwheel of the adjuster assembly to expand the brake shoes. Adjust the brake shoes out until the pressure of the linings against the drum makes the wheel very difficult to turn. Then rotate the starwheel in the opposite direction until the wheel turns freely with a slight lining drag. Replace the adjusting hole cover and lower the wheel to the ground. Repeat the above procedure on all brakes. WARNING Never crawl under your trailer unless it is resting on properly placed jack stands. Follow the trailer manufacturers recommendations for lifting and supporting the unit. Do not lift or place supports on any part of the suspension system.

expert reply by: Mike L