Is a Circuit Breaker Required When Installing Trailer Breakaway Switch?

Updated 09/08/2026 | Published 07/29/2020

Question:

Should we put a circuit breaker on the 12v hot wire between the trailer battery and the breakaway switch? If so, how many amp should it be? Thank you!

asked by: Steeve

Helpful Expert Reply:

When installing a breakaway system and the Replacement Tekonsha Trailer Breakaway Switch # 420000 you asked about, there is no need to add a circuit breaker or in-line fuse. I've attached a help article for the installation of a system as well as a video of an installation to assist.

expert reply by: Jason S

Brad W.

9/8/2026

Recently my trailer experienced an event where the hot wire leading to the breakaway switch shorted out. The wire overheated and the insulation melted, causing damage to nearby wiring and I feel pretty lucky that it didn't start a fire. So while a circuit breaker or line fuse may not be absolutely necessary does it really hurt to have one? Based on my experience it seems advisable that *every* circuit should be properly fused in order to minimize the risk of this kind of event.

Kate F.

9/8/2026

@BradW Thanks for sharing what happened, Brad! That definitely sounds like a scary situation, and I’m glad it didn’t turn into a fire. I really appreciate you sharing your firsthand experience because it gives anyone setting up or working on their breakaway system something important to think about!