Keyboard working but power button not working

hello all,

i recently did a logic board replacement. At first it worked good but after some time i started getting problems:

The keyboard works but the power button does not. I have to turn it on by disconnecting and reconnecting the battery, then reconnecting the charger.

Secondly,

it shuts off with the slightest push on the left side(when its unbalanced, like on my lap).

After that it automatically restarts a few times after which it finally gets to the OS.

I've already tried disabling the sudden motion detector but it does not work.

So any suggestions??

Thanks in advance.