tail lights

Sienna 2003 tail lights does not work .Turn , alarm and head lights are OK .What could be a reason ? I can not beleive if both tail light bulbs went wrong same time .
Thanks

I'm working on this one myself. In your case, the same fuse powers front, back and tailgate taillights (all running lights) as well as the license plate lights. I have a short in my system somewhere. Be careful not to put the bulbs in backwards, it is possible to do so. The blinker filliment burns brighter and will pull too much current.

update on the problem with my tail lights. The van had been clipped and the left front lens replaced. It turns out that the socket in the lens was defective, the ground was in contact with the running light connection. I had pulled all the bulbs to try to find out which one was blowing the fuse and the fuse still blew. I was at the point of pulling harnesses when the I had the thought to remove all of the sockets as well. The fuse didn't blow. I installed the sockets one at a time until the fuse blew. Fixed the defective socket and all is well.