Best Way to Add 7-Way Connector on 2009 Toyota FJ Cruiser for 12V Power to Trailer

Updated 07/02/2019 | Published 07/01/2019

Products Featured in This Question

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp

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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp

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7-Way RV Upgrade Kit for Trailer Brake Controller Installation - 12 Gauge Wires

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Question:

What the best way to add a 7pin connection to my 2009 Toyota FJ. Currently there is no trailer connection. Im only needing the 7pin in order to charge batteries on my tear trailer, no electrical brakes. I was thinking of installing the 4 pin flat wiring package to the back tail lights and running a charge wire from the battery and converting the wires over to a 7-pin. Not sure if this is a good idea. Thanks.

asked by: Scott W

Expert Reply:

The best solution for your application is to install the Tekonsha T-One # 118405 on your 2009 Toyota FJ Cruiser for your standard trailer lights and then add the Wiring Kit # ETBC7L which comes with everything you need to convert the 4-Way to a 4-Way/7-Way and add the 12V function.

Please note that as power runs along that line there will be some voltage drop which will likely keep your batteries from charging completely. To help remedy this I recommend using the Redarc In-Vehicle BCDC Battery Charger 25 Amp # 331-BCDC1225D or 40 Amp # 331-BCDC1240D because they have smart technology that reads what kind of batteries are charging and boosts the power output to match them. The BCDC also has an integrated solenoid to keep your batteries from pulling power when your FJ Cruiser is turned off. You can also add solar panels to them in the future which makes for a perfect combination to go dry camping or boondocking.

I have attached some videos that you can check out.

expert reply by: Jon G