Can I Attach the Tow Vehicles Battery to the Trailer to Charge It

Updated 07/06/2018 | Published 07/04/2018

Question:

have a2015 dodge ram hemi..i want to charge 2 batt, in the trailer. if I use all the Pollock trailer and trk single plugs and attach 1.0 ofw 100 copper wire directly off the batt,??? it has dual alternators ????will it work????

asked by: Victor

Expert Reply:

In order to charge the two batteries you have on your trailer using the tow vehicle you are going to want to install a battery charger for which I recommend using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. This battery charger will use the power from the vehicle's alternator to charge the trailer's batteries and not the tow vehicle's battery. This will also divert the charge back to the tow vehicle's battery once the batteries on the trailer have been fully charged. There is a maintenance feature to ensure they stay charged as well.

The method you mentioned of attaching a large power wire from the tow vehicle's battery to the trailer's batteries is going to be very unsafe and I do not recommend this. There would be no way to regulate voltage or prevent overcharging which would likely drain the tow vehicle's battery. The 12 volt pin on the 7-way is only used to maintain a charge on a small trailer battery and would not be sufficient to charge one.

expert reply by: Conner L