Is a Dead Battery Causing Fuses to Blow When I Plug In My Trailer

Updated 12/15/2020 | Published 12/12/2020

Question:

When I plug in 7 pin it blows fuse. I tested it and open circurt on running and brake lights. My battery is dead on trailer and 15 years old not sure if that could be it. It has a sealed thing called a charger in battery box.

asked by: Butch L

Expert Reply:

There could be a couple causes of this. It could be the battery, since a dead battery can mimic an overload and cause fuses to blow but there also could be an issue with the wiring as you've noticed with the issues on the running and brake lights. I would start by taking the battery to get tested and replaced if needed, but I also recommend going through all of the wiring and making repairs where needed.

I will also say that a trailer battery typically goes bad after this length of time, so replacing it should be strongly considered.

expert reply by: Erik B