idiot oil light

[Link Brian <link@casa.Colorado.EDU>]

My 86 coupe Gt's oil idiot light comes on for a second or two, and the 
relay marked with a orange and white circle and the number "1" on it, 
buzzes.  Ive got oil, oil pressure, and normal oil temp.  My questions 
are--what is the purpose of the relay? And second, is it a sendor problem 
or the relay misfunctioning, how can i tell?.  Any help would be great.-- I 
checked the archieves but couldn't get good matches (my fault i'm shure)

Thanks
Brian link
86 coupe gt 118,000
46 ercoupe O-200