How To Keep The Towed Vehicles Battery Charged When Pulled By RV

Updated 04/15/2021 | Published 04/13/2021

Products Featured in This Question

Roadmaster Battery Charge Line Kit for Motorhomes

(140)

$67.45

Curt 7-Way RV-Style Trailer Connector - Vehicle End

(35)

$13.44

Roadmaster 7-Wire to 6-Wire Flexo-Coil Kit

(248)

$101.44

Roadmaster Battery Charge Line Kit for Towed Vehicles

(1205)

$42.86

Question:

Do I need both part # RM-156-25 for the Escape and RM-156-75 for the motorhome? If so, do I need a connector plug and flex cable between the vehicles that will maintain the 12AGW wire size as required? Do I connect the motorhome charge wires to the RV house batteries or the RVs starting battery under the hood. Can I connect the RM-156-25 wires to the jumper terminals under the hood or do I need to go to the battery under the spare in the rear of the Escape? Please list the parts I need and detailed instructions to maintain my Escapes battery during towing. Should I explore a larger battery for the Escape?

asked by: Andrew S

Helpful Expert Reply:

The best way to keep the battery on your towed vehicle (2020 Ford Escape) charged when flat towing is to use Roadmaster Battery Charge Line Kit for Motorhomes # RM-156-75 and Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25.

The charge line # RM-156-75 connects to your RV's starting battery since this battery is connected to the alternator and will not drain down. Then you will connect the other end of the charge line to the pin in the 1 O'clock position on your RV's 7 way trailer connector. If you need a 7 way for the charge line then it is best to use Curt 7-Way RV-Style Trailer Connector # C58155 and rewire the 7 way and connect the charge line to one of the pins.

Then, connect charge line # RM-156-25 to the center pin on your 6 pole plug (such as Roadmaster 7-Wire to 6-Wire Flexo-Coil Kit # RM-146-7) which is mounted at the front of your towed vehicle. This will run up to the included circuit breaker which is screwed into the metal in your towed vehicle's engine bay. The other end of the wire can connect to the jumper terminals under the hood since your battery is under the spare and is not in reach. You will not need a larger battery for the RV or Escape as the factory battery will do just fine.

I attached several demonstration/installation videos for you to check out.