Configuration and setup ThinkFan on Lenovo T14

Add permissions

sudo chmod 666 /proc/acpi/ibm/fan
sudo chmod +r /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp*_input

Add and activate modules

Create file /etc/modprobe.d/thinkpad.conf and add folowing config

options thinkpad_acpi fan_control=1

# modprobe -r thinkpad_acpi
# modprobe thinkpad_acpi
# modprobe thinkpad_acpi fan_control=1

Find all sensors on your device:

find /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp*_input

Create symlinks for your core temp sensors, because hwmon* - changes dynamically every time the OS boots, for example:

sudo ln -s /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp1_input /opt/sensors/cpu/temp1_input
sudo ln -s /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp2_input /opt/sensors/cpu/temp2_input
sudo ln -s /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp3_input /opt/sensors/cpu/temp3_input

Edit config file /etc/thinkfan.conf

## Thinkfan configuration
tp_fan /proc/acpi/ibm/fan

hwmon /opt/sensors/cpu/temp1_input
hwmon /opt/sensors/cpu/temp2_input
hwmon /opt/sensors/cpu/temp3_input

(0, 0, 40)
(1, 40, 44)
(2, 44, 48)
(3, 48, 52)
(4, 52, 56)
(5, 56, 60)
(6, 60, 64)
(7, 64, 68)
(127, 68, 32767)

Restart and check

sudo systemctl restart thinkfan
sudo systemctl status thinkfan