HP envy 17 laptop will not boot up

I have a HP envy 17 laptop which will not turn on,the battery and CMOS battery seem to test out ok 12v and 3v,the laptop has been dropped at some time which has made a mess of the hindges which I was going to repair but when I got the laptop out to repair it it would not turn on.when the power button is pressed it will flash also the caplock button will flash also the f12 (the WiFi button)will flash.i know the caplock button is used as a fault indicator but it does not flash in a organised way ie,flash slow twice flash three times fast to give a fault diagnosis. It looks like it is in sleep mode all the time so I am wondering if the damage with the hindges have done something to the part that sends the signal to the laptop to go into sleep mode,I have Googled what macanical process puts a laptop into sleep mode with no luck. So I would like to know what macanical part puts the laptop into sleep mode when the lid is closed. Any reply would be appreciated hope this makes sense