Volvo Repair: service light/ dashboard, volvo service, volvo 850

Question
i,ve recently purchased a volvo 850 10 valve 2.5 1995 , manual .
i,m quite mechanically minded and don,t mind getting my hands dirty but the price of a volvo service is considerably more than the price it would cost for me to do it myself .
would anyone be able to tell me , how i can turn off service light , as it lights up everytime i start the car , done the service myself but can,t seem to turn it off , how can i short it out ,

any help would be greatly appreciated ,

Answer
to reset the light turn the key on to position 2 but not started,then under the hood behind the passengers headlight there are 2 small boxes remove the cover for the box with the small wire attached to it ,this bax will be marked A.insert the wire into the hole marked 7 then press the button 4 times for one second each time.the light will light up then press the button 1 time for one second,the light will go out then come on again then press the button 5 times for one second each time,the light will go out then come on againe then press the button 1 time for one second,the light will go out hen it will flash rapidly and go out again,this should have reset the light if not try doing it again sometimes it does not work.