[Bug 2162837] Re: ThinkPad T14 Gen 5 Intel automatically powers on after successful shutdown

I am experiencing the exact same Embedded Controller shutdown issue on a ThinkPad T16 Gen 3 (Meteor Lake).I am running Linux Mint 22 (Ubuntu base) using the Kernel 7.0.0-30-generic.Behavior:Upon triggering a regular shutdown, the system blanks the screen and cuts power for 3 seconds, but then the laptop boots itself back up automatically.Important details & Current Workaround:The machine used to run Windows 11 perfectly fine without any shutdown or reboot loops.As a temporary workaround, I mapped the physical power button to Hibernate. Hibernation works correctly and the laptop remains powered off, confirming this is specifically an ACPI S5 shutdown / EC handshake bug under Linux.Please include the ThinkPad T16 Gen 3 in the hardware list for the upcoming EC/Kernel fixes. -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2162837 Title: ThinkPad T14 Gen 5 Intel automatically powers on after successful shutdown Status in linux package in Ubuntu: New Bug description: Similar to Ubuntu bug #2138359 on ThinkPad P14s Gen 5 Intel, but reproduced on ThinkPad T14 Gen 5 Intel. Hardware Model: Lenovo ThinkPad T14 Gen 5 Intel Machine Type: 21MMS57F00 CPU: Intel Core Ultra 7 155U (Meteor Lake) BIOS: N47ET29W (1.18) Operating System Ubuntu 24.04.4 LTS Kernel: 6.17.0-35-generic Desktop: GNOME 46 (Wayland) Problem After selecting "Power Off" from GNOME or executing: sudo systemctl poweroff the system performs a normal shutdown. The display turns off. The fan stops. The power LED turns off. Approximately 1–3 seconds later the notebook powers on again automatically without pressing the power button. This is not a reboot. The system fully powers off before powering on again. Expected result The notebook should remain powered off. Actual result The notebook automatically powers on again. Troubleshooting already performed - Tested GNOME shutdown. - Tested "sudo systemctl poweroff". - Battery only. - AC adapter connected. - USB mouse connected and disconnected. - Wake-on-LAN disabled. - RTC wakealarm is empty. - ACPI wake sources disabled using /proc/acpi/wakeup. - Latest BIOS installed (1.18). - journalctl shows successful PowerOff. - systemd-logind correctly requests PowerOff (not Reboot). - fwts reports no critical ACPI firmware errors. No change. Windows comparison Windows 11 on the same machine shuts down correctly and remains powered off. History The issue has existed across multiple BIOS versions. The motherboard has already been replaced twice by Lenovo service. The problem remains unchanged. Additional information A complete diagnostic archive is attached (thinkpad_shutdown_bug.tar.gz). This issue appears very similar to Ubuntu bug #2138359 reported on ThinkPad P14s Gen 5 Intel using the same Intel Meteor Lake platform. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2162837/+subscriptions