I replaced the odo gear in my 91 240 wagon, and thought, hey, even though THEY WORK why not put in two new bulbs for the main panel? Now the odo works great, but the dash lights don't. Yeah, I turned up the dimmer etc. etc. Even took it apart and put the old working bulbs back in, no luck. All other lights on the panel work, just not the two main bulbs. Could it just be the contacts? Any thoughts?

 

Go back and check your work. You either damaged the connector or you don't have good contact.