HP 15 Series Laptop | LA-D707P | Power On, White Display | Role of Hall sensor | Can we fix it?

Hi guys, Here we received an HP 15 Series Laptop for repair with a White display when it turns on. After diagnosis we found Hall Transistor problem that was pulling LIDSW# to low. We managed to replace a Hall transistor and repair this motherboard. Just have a look you might be amazed on the working principle of Hall transistor