Where To Access Battery Wire for Install of 7-Way on 2026 Toyota Highlander Hybrid
Updated 03/04/2026 | Published 01/30/2026
Question:
2026 Highlander Hybrid with flat 4 pin connector. Want to convert to 7 pin round and dont know how to access hot wire. Vehicle battery is in rear right side of cargo area behind rear tire. Guidance appreciated. Thanks
asked by: Don W
Expert Reply:
Hey Don, to install a 4-way to 7-way adapter like the part # 37185 you don't have to run a wire to the battery unless you for sure need the 12 volt accessory circuit for like a trailer battery charge. Otherwise it is not needed for the taillight circuits of the 7-way to be active and can be left off. Do you need the 12 volt circuit active? Does your trailer have brakes?
If you need it active it would be a matter of gaining access to the battery in the rear cargo area and connecting the wire to the positive post of the battery.
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Jameson C.
3/4/2026
Hey Don, how did things go with wiring the 7-way adapter on your Highlander Hybrid? Were you able to connect the hot wire to the battery in the rear cargo area? Your update could make it easier for others working on the same setup.