Originally Posted by bigjeep
i've heard that sometimes you have to turn them 180 degrees but if none of them work then that may not be your problem.
I had about half of mine do that. But I installed them one at a time and reversed em if they didn't work. Also, you need to make sure the wire from the bulbs runs down correctly and makes proper contact with the connectors in the twist base. Some of my wiring was off to the side of the bulb's 'blade' that goes into the base.