Question:
I just bought a 2014 Sienna and took off my old hitch before selling my 2007 Sienna. The hitch bolts are in the same place but according to your site, the wiring harness 118304 is not compatible. I see in your installation video for the 2012 Sienna Toyota redesigned the Sienna in 2011 that there needs to be a wire running to the battery, which wasnt necessary in the 2007 model. I am going to try it anyway, but do you know exactly why 118304 wouldnt work for the 2014 Sienna? Did something change with the taillights? What does the wire to the battery do?
asked by: Mark
Expert Reply:
Most modern vehicles have more delicate taillight circuits than older vehicles. The wire that runs to the battery is used to protect the taillight circuits of your vehicle from being overdrawn by the additional load of the trailer lights.
Trailer wiring harness with a wire that runs to the battery use the vehicle battery to power the trailer taillights and then only use the taillight circuits as signal wires.
I can't recommend you install a wiring harness on your vehicle that doesn't have a battery wire. I would recommend you install the part # 118498.
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector