I just purchased a 2000 E39 and can not get the interior courtesy lights to work. No center light, No visor lights, No rear pillar. The the only courtesy lights that work are the ones that project down from the underside of the doors. Map lights also work fine. I have checked all fuses and they are fine. Checked a couple of bulbs and they are fine. Going to check each and every bulb next. My Bentley manual is on order and not here yet. Any other suggestions?