They are GI lights. So it won't be a board problem.
Just thinking out aloud - Have you upgraded to LEDS or replaced / adjusted anything recently ?
I'm thinking there is a short with a common group of GI lamps. A GI Common is shorting somewhere. Follow the GI braid and see if they are all related to the GI lamps that are out. It is going to be something simple. You just need to find it.
