Failure after battery reset X1 Carbon Gen 9

[konanekane]

I've had this two years to the day and it had been terrific. Last night I put in on the charger. Yellow light came on as usual. In the morning though the yellow light was still on. Not usual. I took it off the charger; the yellow light stayed on. Huh? I powered up, the display claimed it was at 73% (up from about 60% the night before) and still charging, which is impossible. I looked up the problem online. The Lenovo site said to press the battery reset button through the pinhole on the back of the case. I powered down, pressed the button as instructed and the yellow light duly went off. However now the unit is completely dead. It won't power on. It won't show a light when I plug in the charger.

I opened it up. Tried disconnecting the battery. Tried disconnecting the CMOS battery. Poked around the battery reset switch. I cannot get a response from the unit. Tried battery out and plugged in. Tried everything I could think of.

Could it be that the battery reset disconnected the battery permanently? Or maybe more likely have I had a failure somewhere in the power chain and maybe I need a new motherboard (might as well just buy a new unit then)?

Any insights greatly appreciated; I can't find anything that helps elsewhere online.

[mikemex]

It depends a lot on how the machine has been used since new. The Gen 9 has weak power charging circuitry so it's best to avoid fast charging (enable plane mode which limits the charging power to 15W) and high CPU TPL PL1/PL2 values (ThrottleStop). Shipping settings on both things are too high and the power circuitry overheats and fails.

I've had my machines since new (got two of them) and never had any issue following such precautions- But if you've used the machine as it comes from factory for a while, there is a chance that the power circuitry has already been stressed out and began failing. It's a common issue with this generation and there is nothing you can do, other than replacing the motherboard.

By the symptoms you describe, that seems to be the case. It could also be that the battery is dead. Those flat batteries just die by looking wrong at them.

[mpcook]

Try the reset button a second time. Unplug the charger first. Make sure the paper clip indeed presses (click) the reset button. Hold it for a few seconds. You can next try a new battery just in case that is the issue. Finally, if you can buy an extended warranty, they will replace the system board.

There is a lot of discussion on the Lenovo forum https://forums.lenovo.com/t5/ThinkPad-X ... 796?page=1

[Orions327]

If you can, open it then look and check near power in socket. You will see 2 tiny components, Q261 n Q263, they are 2 dual N-Mosfet, CSD87501.
Looking by magnifier, is it burned or not? shack by hand make sure they are not leaving motherboard.
Even your problem just happened after reset battery but Dead at all (after you tried to do everything)....maybe we need to look to hardware.
By the way, special for Thinkpad type C PD power charging (viewtopic.php?f=62&t=136400) thank to @mikemex
I had been the same problem before but on a Dell XPS 9550. Just replace a new battery then nothing at all: No power, no light, nothing... after do the same like you.
100% maybe some Mosfet or Capacity is dead, I think. That is not too hard for me to fix but because I have no time, so I put it into my storage with no battery. One month after, one day I take it out to fix....Put power in, press power button....What the hell happened, It works !!!
This is real story, till now, I don't know exactly what happened. If try to explain, maybe it got enough time for all components clear electrical to fresh POST.