Lenovo x1 carbon gen 4th (14282-2m lrv1 mb) no power on

[Xiran]

Hi to all!

I´ve a Lenovo x1 carbon gen 4th, 14282-2m lrv1 mb, wich don´t power on.

I´ve upload initial voltages, in two images

somebody know, where to begin?

I´ve found some brd view and a pdf

Thx in advice!

[mon2]

Hi.

1) review the charger bible by piernov that is linked above.

2) the dcin mosfet with 20v is a suspect. Share the part # on this mosfet. Most likely to be defective.

To confirm, remove all power. Meter in resistance mode.

Measure the resistance across:

source / drain
source / gate
gate / drain

Post all measurements. Each should be hundreds of k ohms or higher else may be defective.

[Xiran]

Hi.

1) review the charger bible by piernov that is linked above.

2) the dcin mosfet with 20v is a suspect. Share the part # on this mosfet. Most likely to be defective.

To confirm, remove all power. Meter in resistance mode.

Measure the resistance across:

source / drain
source / gate
gate / drain

Post all measurements. Each should be hundreds of k ohms or higher else may be defective.

Thx for your answer mon2!

The diagram says:
Q6910
TPCC8131-GP

source / drain = 1 Mohm
source / gate = 1 Mohm
gate / drain = 1.2 Mohm

[Xiran]

Everything seems to point to damage to the processor... checking for shorts, the data lines of 2 USB ports are in low impedance, I trace the lines, remove connected components, but the short persists, the line now goes directly to the processor