How to Charge a Camper Battery with a 6-Way Connector on Pop-Up Camper and a 4-Way on Tow Vehicle


Product 118412 wiring harness is designed for use in the Toyota RAV4. The plug is a four prong flat and my pop-up camper has a 6 prong flat connection. The camper refridgerator can be run off the camper 12 volt battery while towing, but the battery needs a feed from the tow vehicle to stay charged. How do I do this and not exceed the amperage allowed by the wiring harness?

Expert Reply:

I would recommend to use the Hopkins 4-Way to 7-Way and 4-Way Adapter, part # 37185. This adapter will install on your 2011 Toyota RAV4 and allow you to have a 7-Way connector and also a 4-Way connector. You would plug in the 4-Way on your vehicle to the back of this adapter. There will be four remaining wires on the back of the adapter.

The white ground wire will need to be attached to the vehicles frame. The black wire on the adapter will need to be connected to the vehicles positive battery terminal with a length of 10 gauge wire (# 10-1-1) using a 40 amp inline circuit breaker (# 9510). This is the wire that will supply the power to charge your trailer battery. Since it is not running through the vehicles wiring harness it will not cause any problems with the wiring harness.

The other two wires are blue wire for electric brake controller and the purple wire for reverse lights or auxiliary power. If these wires are not needed they can be taped up out of the way.

For the pop-up camper, you will need to remove the 6-Way flat connector and install the Hopkins 7-Way Molded Trailer Wire Connector, part # H20042, to the wires on your trailer. The wires on the pop-up camper will be attached to the Hopkins connector according to the color code listed in the product description, with the black wire attaching to the positive terminal of the trailer battery for charging.

You will want to make sure to unplug the trailer when the vehicle is not running to avoid discharging the battery on your RAV4, or you can install the Tow Ready Battery Isolation Solenoid, part # TR118665. This solenoid will need to be installed in-line with the 12 volt power wire and a lead ran to a circuit that will only be hot when the ignition is turned on. This will keep the battery from pulling a charge unless the vehicles ignition is on.

I am including a link to a FAQ page on trailer wiring.

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