Cruise Control and Dome/Courtesy Lights

Fuses control power to both of these system. The cruise related fuses are the RLY IGN1 fuse in the trunk which powers the cruise control switch and the CRUISE fuse under the hood which powers the cruise control module. The dome lights are powered by the INT LPS fuse under the hood. If as you say all these fuses are good then it may be a good idea for you to have these systems diagnosed by a qualified technician. There may be two different problems causing these two different system to not be working.

I have the very same problem with my 1998 deville. My lighter is also out. Let me know if you find a solution.