??? I don't think we have fuses for a brake light bulb.
The bulb just blows when there's a problem. I think the earlier e38s (like yours) have some issues with corrosion around the brake light sockets. Maybe check yours to see if your bulbs are making good contact with the sockets?
Not totally sure what the problem is you're experiencing......
2000 740iS. MKIV, 16x9, DDEs controlled by Euro fog light switch, reversed steptronic +/- pattern, paddle shifters, clear corners, Basslink, iPod video with stereo audio, TV tuner, gauge rings, ///M pedals, backup camera with 'on demand' switch, quad brake lights, Dinan engine & tranny software, windows/sunroof close via remote.
2003 540iS. MKIV, 16x9, PDC, CWP, TV tuner, backup camera with 'on demand' switch, paddle shifters, windows/sunroof close via remote, iPod video & audio.