#3,5, or 9. Actually, just open the fuse box and look. You'll be able to see at a glance if any of the fuses have blown. Those fuses are all 8 amp. I didn't have any interior lights as well and it turned out that the PO had installed an incorrect turn signal bulb that kept burning out the fuse. Once I replaced the bulb with a correct one, I had lights!!! Good luck!

__________________
1987 300e "200,000+ and going strong"