Can a Trailer Battery Be Charged Using 7-Way Trailer Connector

Question:

How do I wire my trailer , so that my truck will charge the tounge battery

asked by: Ron

Expert Reply:

On a 7-Way trailer connector there will by a 12 volt circuit. On the trailer side 7-Way it is the wire located in the 1 oclock position if looking at the back of the connector where the wires attach. Or if looking at the front of the connector it would be in the 11 oclock position.

You would attach the wire from the 12 volt circuit to the positive battery terminal on the trailer mounted battery.

This will provide a maintenance charge only. It cannot charge up the battery. the reason for this is that the truck alternator cannot push back the amperage needed to charge up a full sized 12 volt battery (it can however charge a small break away system battery). Also, the wiring used in tow package wiring and trailer wiring is not rated high enough for the amperage, even if the truck alternator could push it back that far.

Using an AC charger like # CTEK56353 is the ideal way to charge a battery.

expert reply by: Michael H