HP Pavilion 15t-au000 won't power on

[TrunkMonkeyUT]

I have a 5yo HP Pavilion 15t laptop that won't power on.  Was working fine, plugged in to charge overnight, next day, wouldn't power on.  Here's some info and troubleshooting I've tried:

- when the power button is pressed, the LED on the power button lights up for a moment, then turns off.  Nothing else happens - no fan or BIOS start

- appears to be charging normally, let it sit for several days while waiting for power button and when plugged in, shows orange charging light

- have replaced the power button and motherboard with known working ones, same issue

- have checked power from power port to mobo, showing 19.x volts

- pulled SSD drive and plugged it in USB to another system, everything normal

- replaced BIOS battery, no change

- have tried the reset (no battery, hold power button down), no change

My next guess would be the power port, but with the multimeter showing the mobo getting power and the power button light coming on even for a second makes me think it's getting power.  Just somewhere there's a disconnect to sending/triggering power to the mobo to boot.  If the switch that senses the lid is closed were bad, would it not allow the laptop to power on?  Any ideas?

[TrunkMonkeyUT · Accepted solution]

Ended up being the voltage regulator.  Had a repair service on Ebay look at it and fix it.