[jeffc]

Well, after some searching on the web I could find nothing of use so I called my dealer. Don't get me going on the dealer, I have 3 Toyotas, this is the first new one I've bought and the dealer is rapidly making me think twice about this purchase.

Anyway, after some round-about talk, I figured out that I need a special-order trailer wiring adaptor for $150. This reportedly has 5 wires "in" and 4 wires "out".

HA!

I guess I can get an after-market one for $25 or so but that may affect my warrantee. Anyway, this answers the question on how pre-wired for a trailer a 2005 Sienna is, I don't know if an '06 is the same or not.

- jeff