MacBook Pro wont turn on anymore

Hello my dudes,

maybe you can help me somehow.

To explain the situation:

I’ve got this macbook pro with a half working keyboard. I changed the keyboard and everything was working great but I noticed that the Bluetooth and Cam weren’t working anymore. After trying everything out I reattached the iSight cable. Bluetooth and Cam started to work again but wlan wasn't. So after cleaning the connectors and reattaching the cable carefully back again the MacBook pro wasn’t turning on anymore.

I tried to disconnect the Battery and reconnect it. Change the Battery out with another one. I disconnected the keyboard from the logicboard. I tried to use the two pins on the logicboard to manually try to start the mac. Nothing worked. The chargers indicator light shines bright green and the battery indicator shows 7 green dots from 8.

After doing some research I checked the g3Hot rails and they all were fine. Maybe you have some guesses on what could be the problem with this logicboard/macbook pro.