IOk. On the side of the laptop where the USB ports are that are part of the function board and where the adapter jack is located are two leds . One is for the battery charging port that when the adapter is plugged in is either orange or blue depending on the batttery charge . That one is fine ; howeve, there is another LED right next to that one that lights blue when the unit is turned on whether the unit is powered by the adapter or battery. That is the one that is not lite.  Otherwise ,the computer works fine.

The motherboard is the exact same part number as the one that was replaced and it is a new one. I double checked all of the connections on unit for lose or unconnected cables and they are all connected and secure.   So I don't know . I cannot find a On/Off power switch or board on this unit as I can on my Dell or HP. I did have to replace a LCD display cable as the one that came with  unit broke when removed from faulty MB but that part # is the exact same pt # of cable that came with unit. Unfortunately Acer does not offer an online service manual as does Hp or Dell . That make it really difficult to locate parts on Acer units. I have no Idea how to repair his problem. thanks

There is no connector from the led s to the motherboard. on the old Mb or new MB . When i remove the function board where leds are located there are two pieces of plastic imbedded in the top cover or I guess Palmrest where the key board is. The on/off button is part of the keyboard. On the keyboard the on/off button is about an inch from where the LEDs are located on the side of unit . There are no connectors from the MB or function board connected to them. The function board just sits on top of them and has two screw that connect it to the MB while a cable from it connects to a connector on the MB which then has a cable from he same connector that goes to the touchpad. Otherwise, that's it