Why Should I Run the Trailer Power Wire Directly to My Battery Instead of a Vehicle Power Source?
Updated 09/02/2025 | Published 08/15/2025
Question:
Why wire directly to the battery and not a vehicle on power source?
asked by: Earl M
Expert Reply:
Hey Earl!
The thought process behind running the Curt T-Connector # C29ZV wiring harness power wire up to the battery is so that your trailer lights won't be drawing power off of any circuits on your 2025 Hyundai Santa Fe. It offers an extra level of protection both for the circuits on your vehicle, and to ensure that your trailer lights won't go out due to too much power being drawn from any given circuit in your vehicle.
We've had a handful of people ask this question in the past and while I definitely see the reasoning behind it, when it comes to towing, I'm all about the safety side of things and that's ultimately what it boils down to; getting to your campsite/vacation/outing safely.
I've installed similar kits on a few vehicles here in our shops at etrailer as well as one at home on my 2010 Town and Country. It was definitely easier running the wire on a lift, but it also wasn't too bad on my van either. I installed my hitch and the wiring at the same time so I just backed my van up on the ramps I use for changing oil and it gave me more than enough room to mess with the wiring at the back and run it up to the front.
What do you plan on using the wiring kit for? Towing, or another accessory (like a bike rack)?
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Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
more information >
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Jon G.
9/2/2025
Hey Earl, How did the installation of the wiring kit go for you? I'm curious to know if you found it straightforward or if you ran into any challenges, as your experience could be helpful for others considering similar setups.