How To Keep Towed Vehicles Battery Charged When Flat Towing

Published 09/02/2021

Products Featured in This Question

Curt Tow Bar 7-Way to 6-Way Coiled Adapter Cord w/ 6-Way Socket - 7' Long

(115)

$97.96

10 Gauge Wire - Blue Primary - Per Foot

(104)

$1.84

40 Amp In-Line Circuit Breaker - Perpendicular Mount Bracket

(97)

$9.84

Ring Terminal - 12-10 Gauge Wire - 3/8" Ring ID

(69)

$1.67

Roadmaster Battery Charge Line Kit for Towed Vehicles

(1199)

$43.49

Question:

I flat tow a 2015 Equinox. I use a 7 pin to 6, cord and socket on the car. The center pin aux is hot. Can I use this to keep the battery in the car charged when towing?

asked by: Curtis L

Expert Reply:

Yes, you can utilize the unused 12v pin on your 7 way and 6 way plug in order to keep your towed vehicle's battery topped off. Keep in mind, this will only act as a battery maintainer / tender but it will not charge a completely dead battery. It sounds like you are using a kit like Curt Tow Bar Extension Cord w/ Socket - Coiled - 7-Way RV to 6-Way Round - Cord # C59HR in which case you simply attach a wire to the 6 way center pin (12v) and then run it to the positive terminal on your tow vehicle's battery.

To do this you can use a handy kit like Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25, or just run some standard wire 10 Gauge Primary Wire - Blue - per Foot # 10-1-1 along with 3 Ring Terminal # DW05705-1 and a 40 Amp In-Line Circuit Breaker # 9510. I attached a demonstration video for you.

expert reply by: Andrew N