HP Probook 4421s no power

[A1yn88]

Hello guys,
i have a hp laptop with 19v but no 3.3v, no 5v and no power led.
I change RT8206B in which the current that is on the schematic get in but does not come out. Does need some signal from somewhere or just have bad luck and I installed a bad piece?

[piernov]

Re: HP Probook 4421s no power

As always you have to check the power supply rails going to the chip and its enable signals.
IN, VCC are the power rails, ONLDO, ON1, ON2 are the enable signals.
In the specific case of the 3V/5V regulator, usually the LDO is always activated but the buck converters are activated by the EC.

[A1yn88]

Re: HP Probook 4421s no power

IN - 18.48v
VCC - 5v
ONLDO - 5v
LDO - 5v
REF - 2v
I olso have 5v on pin 17, 19, 20, 24

[Techtiger]

Re: HP Probook 4421s no power

Check also ADP_ID Detected by SIO

[A1yn88]

Re: HP Probook 4421s no power

Check also ADP_ID Detected by SIO

You were right. Thank you.
The PD35 diode was short circuit and the circuit from ADP_ID to PD35 was interrupted.

[A1yn88]

Re: HP Probook 4421s no power

[Techtiger]

Re: HP Probook 4421s no power

So did you replace diode? Is the Mob working?