I had a 3-LCD projector go wrong in two different ways. Thankfully it was easy to fix, but this information was deeply buried in a forum for home theatre enthusiasts. The manufacturer would tell customers to buy a new one.
(Are the panels out of alignment? There’s a secret service menu to fix it easily! Do you have discoloration creeping in at the top & bottom? Remove the cover and just push down on the little plastic thing next to the lamp!)