HP EliteBook 840 G1 6050A2560201-MB-A03 Not turning on

[REpairAT]

Hi,
the problem: As soon as charger gets connected, Power LED lights up for a second, battery is charging normally, just does not turn on.
Voltage on power button is 2.3V, which looks too low for me. Lid sensor, SIO, BIOS chip etc. all get full 3.3V. Got the schematic already, but without boardview I'm stuck.

Any ideas? Thanks!

BR, Ray

[mon2]

Re: HP EliteBook 840 G1 6050A2560201-MB-A03 Not turning on

Where are you measuring this 2v3 voltage?

Remove all power -> measure the resistance to ground of this same pin.

[REpairAT]

Re: HP EliteBook 840 G1 6050A2560201-MB-A03 Not turning on

Where are you measuring this 2v3 voltage?

Remove all power -> measure the resistance to ground of this same pin.

Measure taken from button itself on SUB board.
Towards ground, 4.7MOhm, goes to zero if button is pressed.

Edit: Measurment is the same, if SUB Board (Power Button, LED, Lid Sensor) is disconnected.

[REpairAT]

Re: HP EliteBook 840 G1 6050A2560201-MB-A03 Not turning on

Just checked Pin 72 on SIO controller, which is responsible for ON/OFF button, measures 3.3V and goes down to zero when button is pushed, so issue must be somewhere else, probably BIOS. I will check this next tomorrow, as it's this weird 2-chip layout.