What is Correct Gauge of Wire for Wiring Trailer Brakes

Updated 09/09/2019 | Published 09/06/2019

Products Featured in This Question

Dexter Electric Trailer Brake Assembly - 10" - Right Hand - 3,500 lbs

(303)

$83.92

10 Gauge Wire - Blue Primary - Per Foot

(108)

$1.61

Question:

I just purchased a new 20’ tandem axle car hauler. Only the rear axle has electric brakes. The front axle is an idler. I replaced the cheap 7 prong plug that came on it with a quality sealed plug with j-box. I’m getting power to the brakes, but I’m not sure it’s enough to fully activate them. The wire size seems a bit small to me...maybe 14 or 16 ga. I know 12 ga is recommended. I’ve adjusted the pads out to a slight drag. The brakes all work well on my old car hauler and travel trailer, so I know it’s not on the truck side. I even removed both hubs and all looks good inside, and the arm engages the pads when moved manually. Everything else appears fine too. No shorts, no broken wires, and a good ground. Everything keeps pointing me to the wire size. Could that alone be the issue?

asked by: Randy S

Expert Reply:

Yes the issue is related to the wire gauge you have. You need to go with 10 gauge wire like part # 10-1-1 (sold by foot) to deliver the amperage and voltage needed for your brakes to activate. 14 or 16 gauge wire is no where near heavy enough for this task.

expert reply by: Jameson C