[help]lenovo thinkpad 16s gen 2 TOTALLY DEAD

[phantomEVO]

Hi to all! thinkpad p16s gen 2 totaly dead. i have only 5v on both ports.

pd controller is tps65994

i don't know where to start: could you help me? thank

Schematic & Boardview - https://www.badcaps.net/forum/troubl...atic-boardview

[reformatt]

This has a NVDC power supply, so should boost the USB-C 5V to around the battery voltage. So first thing to check is for a short on the B+ rail, then presence of your +3V LDO. 20V negotiation is irrelevant.

[phantomEVO]

hi reformat thank you for your answer...

i don't know what is a nvdc power supply

battery has very very low voltage

on the pd controller i have

5v ON DOCK_VBUS20

0v on Vin3,3

5v on Charger in

3,3v on Vcc3 Ldo

now what can i check?

Thank you

[mon2]

https://forum.monolithicpower.com/t/...power-path/162

[phantomEVO]

Thank you...so ..what could be the next step?

[mon2]

0v on Vin3,3

?? Suggest to use the exact netname from the schematics otherwise it becomes a game of 'Where is Waldo?'. Our PCB designer does the same often and we have to spend time to hunt for the new label created in his head.

Where was the above measured?

To me, if the Vbus voltage is not 20V then there is something wrong with the PD controller. The PD controller is often a stand alone negotiator for the power delivery contracts. Provided the firmware is ok and the pd controller is not defective, the Vbus rail should be @ 20v, supplied by the power adapter.

Any power rail that is @ 0v or not in the normal range, test its resistance to ground (without power to the board) to check if the rail is shorted or not.

[phantomEVO]

all measurements done on pd controller no shorts on the pd controller

with vin3,3 i mean vin_3v3

[mon2]

This is of concern since the rail is also used by the PCH (CPU).

Remove all power. Meter in resistance mode. Measure the resistance to ground of VIN_3V3. Checking if there is a shorted part on this rail. What is the exact resistance in ohms?

[phantomEVO]

25k

[phantomEVO]

even with another pd controller, i have the same behaviour