Adding a Battery to a Snowmobile Trailer for Interior Trailer Lights
Updated 05/29/2020 | Published 09/07/2011 >
Products Featured in This Question
Question:
Hi, I have an enclosed snowmobile trailer w/electric brakes and inside lights. I would like to add a battery to turn on lights when not connected to my truck. What is the best way to do this? thanks
asked by: Brent
Expert Reply:
Start with mounting a battery. Since the trailer is enclosed, it would be a good idea to mount it on the trailer frame using a battery box like # 329-HM318BKS. Next, you will need to have the right kind of connectors on the truck and trailer. I would use a 7-Way RV style if you do not already have them on the truck and trailer.
There is a 12 volt circuit on a 7-Way. You can run a wire from the 12 volt circuit on the trailer side connector to the positive battery terminal. The battery should be grounded to the trailer frame. The 12 volt hot lead will maintain the trailer battery, though it will not be able to fully charge it.
With the battery installed, you will want to wire the lights to it. The lights will have a power wire and a ground. The power wires for the lights is currently connected to the 12 volt circuit from the trailer connector. You will need to instead route the trailer light power wires to a switch, like # BL0108-00, using a spade terminal. Using another spade terminal, connect a length of wire to the positive battery terminal. Hit the switch and the lights will turn on, running off of the trailer battery. They will no longer come on when connected to the truck via the 7-Way connector because the lights cannot have 2 power sources.
Featured Help Information
Miscellaneous Media
Continue Researching
- Search Results: battery box
- Q&A: How To Wire and Install On-Board Auxiliary Trailer Battery to Power Lights
- Shop: TorkLift PowerArmor Locking Battery Box - 6V and 12V Lithium Batteries - Powder Coated Aluminum
- Video: Snap-Top Battery Box with Strap for Group 24 to Group 31 Batteries: The Breakdown
- Video: A Closer Look at the NOCO Snap-Top Battery Box with Strap
- Shop: Kenda 215/60-8 Bias Trailer Tire with 8" White Wheel - 5 on 4-1/2 - Load Range D
- Q&A: Adding Interior Lights to Trailer and Keep Battery Charged
- Q&A: How To Install a Battery On a Trailer for Use with Electric Jack
- Q&A: How To Wire In A Trailer Battery To A Horse Trailer's Electrical Systems
- Search Results: battery boxes
- Video: MAXXAIR MaxxFan Mini Plus Manual RV Roof Vent Installation - 2022 Grand Design Imagine Travel Traile
- Video: In-Depth Review of the TorkLift PowerArmor Solar Locking Battery Box
- Shop: Commercial Grade Battery Box for Group 8D Batteries - Vented
- Shop: Commercial Grade Battery Box for Group 4D Batteries - Vented
- Shop: Snap-Top Battery Box with Strap for Group 24 Batteries - Vented
- Shop: Snap-Top Battery Box with Strap for Group 24 to Group 31 Batteries - Vented
- Article: Trailer Wiring Diagrams
- Search Results: e track
- Search Results: trailer tongue battery box
- Shop: Ventline Ventadome Roof Vent w/ 12V Fan - Powered Lift - 14-1/4" x 14-1/4" - Smoke
- Video: Complete Breakdown of the B and B RV Horseshoe Vent Cover
- Video: An In-Depth Look at the Ventline Ventadome Roof Vent w/ 12V Fan
- Q&A: What Type of Battery Works Best for Powering Trailer Interior Lights
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Shop: Trailer Hitch
- Search Results: trailer hitch
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Shop: Trailer Wiring
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Search Results: trailer tires and wheels


Shane C.
5/24/2020
If I’m using a junction box for lol the connections, do I run a wire from + on the battery to the junction box where the 12v acc wire, 12v circuit from 7-way, and black 12v wire from electric brakes are connected? Should I add a fuse to any of those circuits? I’m curious if there’s any problem with the electric brakes breakaway kit battery and the trailer battery battery being connected together. Or the interior lights being powered by the battery and 12v circuit from 7-way. Thanks for the help.