Hi @gensin ,
Don’t know the answer here’s an image from the schematics for the motherboard, (I think they are the correct schematics anyway) showing the power button board circuits. I’ve highlighted component CN9200 which fits the description that you’ve provided.
(click on image to enlarge for better viewing)
Searching online using the information written below the component i.e. ACES_50503_0044N_001_4P gives no results as to what it is other than it is also used in other makes of laptop computers. Unfortunately there is no parts list as such, associated with the schematics describing each component, only what is written on the circuit diagram.
I’m wondering if it is a sensor (switch?) for the lid and signals when the lid is open and shut so as to either place the laptop in sleep mode or to turn off the screen when the lid is shut, depending on the power settings etc. Just a thought.
If it is the lid sensor (check if lid functions when set in advanced power options work e.g. sleep when lid closed, turn on when lid opened etc, if not, then it may be easier to get a replacement power board than to find the elusive part. Here are the part numbers for the power board taken from the hardware maintenance manual (see p.86)
Power button board (includes cable) For 15.6-in. models 738701-001 For 14-in. models 738399-001
If you search online using the appropriate part number only you’ll get suppliers of the part
Hopefully this may be of some help.