I'm with budkorn, as it's worked in my 300TE. Seems like if I try to reset it when I'm not moving, it never kicks in but makes an audible (and annoying) "click" every few seconds. I hold the button in while moving, and eventually it catches and I'm on my way.
Pain in the butt, so I simply don't use the trip odo often. However, I've got a few illumination bulbs out in the cluster so I'll deal with it then.
Best regards, Michael