Ok so i was played for a vehicle and ended up with a 1997 BMW 740 IL thats a lemon...Anyway today I went to the junk yard to get a few sockets for the tailights because I noticed alot of them was missing...I put brand new bulbs in them and they work...I noticed i did not have any brake lights at all but i have parking lights...SO i placed a socket into the brake light area and it did not work so i removed one of the parking lights and placed it in the brake light area and still no luck...So i take the thing to a mechanic and he tells me that i need a circuit board for both tailights for the brake lights...So a good friend of mine who is a mechanic put the sockets in place and the left brake light worked but the right brake light would not work...Im confused because i was told i need a circuit board but yet I have 1 brake light that actually works now so my question is....Do you think it may be corosion around the socket brackets? or do you think i really need a circuit board...But mind i was told that i need it for both but now 1 is working...Any suggestions would be greatly appreciated seriously...Thanks for the help