[jeffc]

I'm sort of in the same boat, I have multiple trailers and tow vehicles so I want to have them all be compatible. I am used to a trailer wiring set-up that has a ground, a running light and left brake/turn and right brake/turn (4 connectors). It seems like the Sienna has separate brake - running light - right turn - left turn - ground (5 connectors?!?!?), so if I figure anything out, I'll post it. I wired the trailer up by taking off the rear lights and soldering in new wires to the wires feeding the rear lights, I plugged in my trailer and then realized that I only had turn signals, no brake lights. I have a 2005 Sienna.

- jeff