2001 Volvo S80 Brake Lights

Hi, and thank you for your reply I am looking at the owners manual at the moment it shows exactly where the fuse box in the cargo compartment is where I already have looked at the related fuse which is perfectly fine! Unless you are tallking about the the main fuse box (big black fuses) which is located in the same area directly next the fuse box and which the instruction manual strictly advises not to be changed except by and authoraised person and therefore the owners' manual does not say which black fuse does what. I would be very grateful if you could let me know where that bad relay is and I shall declare my self an authoried owner for one day and change it myself! I have already had a couple of so called authorised pepole look at the problem and all I got from both of them is no electricity is reaching those lights (as if I already did not know that) one of them even made me buy a brand new brake light switch. Thank you again for your help and I look forward to your next reply.