Laptop doesn't turn on after changing the screen backlight

[vesko]

My old laptop Fujitsu Amilo Li3710 doesn't turn on after I changed the screen backlight. The fan doesn't start and the power LED is off. The battery indicator is blinking which means the battery is charging and there is electricity going to the laptop. Any ideas what might be the problem?

 

[webworkings]

I would open it back up and make sure nothing got knocked loose or disconnected when you were doing the work. Happens all the time.