Laptop Repair 002 - Thinkpad X220 No Charge, No Power (TPS51220 problems)

This video shows basic diagnosis of faults on standby power rails, usually 3.3V and 5V for SMBUS and other standby functions. It's controlled by a chip similar to this TPS51220a which drives both rails.

[@oefzdegoeggl]

yeah i am currently fighting with a board that has none of the enable signals on the TPS present. so i disconnected all enable signals from the rest of the board and frankensteined the VREG3 onto it. now 3.3V and 5V come up. i have more problems on this because the sense signals on the SIO (3.3, 5, 12) are missing (though SIO is up and reads the powerbutton). so there seems to be some deeper problem in this board. i have no schematics ready with any TPS, do you have a hint maybe where the enable signals usually come from?

[@TractorPowerPL]

I have 3 not working X220 Tablet version laptops. Since I have issues finding anyone in Poland who would repair older Thinkpads. Can you help? I can send them by UPS or DHL