Is Wire Size on a 4-Way Large Enough for 12 Volt Power to Charge a Battery

Updated 03/07/2018 | Published 03/06/2018

Products Featured in This Question

Hopkins Endurance Easy-Pull 4-Flat Extension w/ 1 Grip Ring - Vehicle and Trailer Ends - 12"

(21)

$10.56

Bulldog Winch Wiring Kit for ATV/UTV Winches - 96" Long Power Lead

(5)

$49.99

Question:

I am setting up a 2016 Jeep Cherokee to flat tow and, given this is also my main commuting vehicle, I am wanting to hide my wiring connectors and break away switch behind a fold up license plate arrangement. From the RV to the Jeep I am planning on using a Roadmaster 7-Wire to 6-Wire Straight Cord Kit - 6-1/2foot Long Item # RM-98146-7. I am also installing a SMI Stay-IN-Play DUO Supplemental Braking System - Proportional Item # SM99251 in the Jeep for the breaking system. I will use the Roadmaster Battery Charge Line Kit for Motor Homes Item # RM-156-75 and the Roadmaster Battery Charge Line Kit for Towed Vehicles Item # RM-156-25 to charge the Jeep battery. Due to size constraints only a 4-pole flat connector will fit behind the license plate. The Jeep Cherokee needs a 12V line to keep the battery charged during towing and the Stay-IN-Play needs a connection back to the RV for the Coach brake signal. I was thinking of using two 4-pole flat connectors, 1 for the light harness and ground and 1 for the 12V power and coach brake light to hide behind the license plate. I would use one trailer side connector and one vehicle side connector to ensure they cant be plugged into the wrong place. Is the wire gauge size on these easy pull connectors large enough for me to use them as direct wire pig-tail adaptors on the Jeep side of the 7-wire to-6 wire straight cord for the 12V battery charge line?

asked by: Keith L

Expert Reply:

Basically, yes and no. Given the short distance from the front of the vehicle to the battery the small gauge wire on # HM48144 would more than likely be able to handle the amperage running through it. But the greater the distance the less amperage it can handle. The problem you will run into using 4-Ways is the small wire gauge.

As an alternative what about using some winch wiring and connectors, # BDW20306. The connectors aren't much larger than a 4-Way and the wire gauge on these is larger to safely handle the power running through.

expert reply by: Michael H