Here's the service manual and parts list:
[link|https://www.manualslib.com/download/1603125/Hp-Pavilion-X360-14-Series.html|HP Pavilion x360 14 Series Maintenance And Service Manual|new_window=true]
[link|https://support.hp.com/nz-en/document/c06519297|Parts List|new_window=true]
***Power button board***
[quote]The power button board spare part kit does not include the cable. The cable is available using spare part number L51094-001.[/quote]
L51112-001
This may help.