Take a look through this site's documentation for your year, there may be some information there. I have a '95 Marquis Garnet 300 and my panels seem to be working correctly. I have no information in my coach's documentation on the CMP. If you are willing, power everything down and pull it out to look at the backside, as Yogi Berra said, "you can learn a lot by just looking". I suspect something is fried after 27 years. If you have any questions about your coach, contact me, I have been fixing the issues with mine since a bought it a year ago.