Can I Charge Trailer Batteries Using The 12V Aux Terminal On A 7 Way Plug

Question:

Would I be able to wire a 7 pin make plug to charge a 12v battery inside my trailer using the female hitch plug on my truck? Picture added for reference of where the idea came from.

asked by: Gabriel C

Expert Reply:

Yes, the 12 Volt auxiliary terminal (red) on your 7-way connector can be used to keep the battery on your trailer charged. You will need to run a 10 gauge power wire like # 10-1-1 from the 12 volt auxiliary terminal on the 7-Way trailer connector on the trailer to the positive terminal on the trailer battery and ground the negative terminal of the trailer battery to the trailer frame. If your trailer does not already have a 7 way plug, you can use a 7-way plug # PK12706 along with some 7 wire # DW04914-1, which is sold by the foot.

It is important to note that this will allow you to maintain a charge on your trailer battery, it will not charge the battery from a discharged state.

expert reply by: Jesse M