Can The Electric Tongue Jack EJ-3520-BBX Be Powered By 7-Way?
Updated 11/17/2025 | Published 12/05/2024
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Question:
If I install this on a 2001 Sundowner 2 horse trailer, that doesnt have a battery to connect it to, I will need to connect it to my 7 pin wire harness and power it from the truck. What additional components would I need to order? ie. Junction box?, etc? Thanks....
asked by: Marc S
Expert Reply:
Hey Marc. Adding a battery to the trailer is definitely the best way to power an electric tongue jack like the # EJ-3520-BBX. That said it is possible to wire it to the 7-way, and there are two ways to do this.
Option 1: Add a junction box like part # e99009 and wire it to the 12v power post of your trailer's junction box to have it pull power from the trailer's 7-way when connected to the tow vehicle.
Option 2: Wire it to its own plug # PK12706, with the wire connected to the 1 o'clock position of the plug, and then you can plug it in to the tow vehicle's 7-way to power it.
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Electric Jack w/ Footplate - A-Frame - 25-1/8" Lift - 3.5K - Black
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- Teardrop Camper
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- 3001 - 4000 lbs
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Jesse M.
11/17/2025
Hey Marc, how did things go wiring the electric jack on your Sundowner trailer to the 7-way connection? Your experience could point others in the right direction when deciding between adding a junction box or using a separate plug.