Here's how you can disable the red LED in the ThinkPad logo:

Prerequisites

You need a kernel compiled with CONFIG_THINKPAD_ACPI_UNSAFE_LEDS=y and the boot parameter ec_sys.write_support=1 set.

Manual

Run: echo 0 | sudo tee /sys/class/leds/tpacpi::lid_logo_dot/brightness

systemd service

This systemd-service disables the red power LED …

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