La-d401p Schematic ((install)) -

Once you locate a legitimate (usually a PDF file), focus on these critical pages.

The LA-D401P is a compact, high-density motherboard designed by Compal Electronics for HP’s premium Spectre line. Because the HP Spectre 13 is exceptionally thin, the board utilizes highly integrated components to save space. la-d401p schematic

Phase node of VCC_CORE (drain of high-side PQ501). You should see a square wave from 0V to 19V at 300kHz. If you see 19V DC with no switching, the controller is not receiving VR_ON. Once you locate a legitimate (usually a PDF