dash lights dissappear after 5 p.m

Hi This is my first posting so I hope I'm doing this correctly. We have a 1998 Aurora that keeps loosing it's interior dash lights-ac,radio,dash board-every day at 5 p.m and they don't come back until about 9 a.m This has been happening since about May. I've seen some posting for the twilight sentinel switch and wondered if any other owners of the Aurora having this same problem have come up with the solution. I look forward to some replies. Would like to get this fixed before fall and the time changes. We're in Southern Ontario. Thank you Joner54

Please find the correct forum for this. You'll get better answers there.

http://home.comcast.net/~ec437/obvious.JPG