I have a Mitsubishi WD-65837. A couple weeks ago, I started getting an error code 57. I took out the electronics and gave them to a friend to look at, since none of the caps on the ballast looked bad. He said a couple on the main board tested kinda iffy, so he changed them out. Everything looked fine on the ballast. I still get an error code 57. He suspected a faulty chip on the main board, but could offer no further assistance.
He's suspecting the main board, which is a little tough to find. I don't really want to buy a ballast if that's not the problem.