Fixing CPU fan on Lenovo Thinkpad T520

Issue: CPU fan on Lenovo Thinkpad T520 is always on.

OS: Ubuntu 10.04.3 LTS Lucid Lynx with backported kernels from Oneiric.

Source used for solution: Ubuntu Forum , — thanks to user mejo

Solution:

1. install thinkfan package:

$ sudo apt-get install thinkfan

2. add kernel module ‘coretemp’ to /etc/modules

$ sudo sh -c ‘echo coretemp >> /etc/modules’

3. load kernel module ‘coretemp’

$ sudo modprobe coretemp

4. add the following three sensor entries to /etc/thinkfan.conf just before the temperature levels:

sensor /sys/devices/platform/coretemp.0/temp1_input
sensor /sys/devices/platform/coretemp.0/temp2_input
sensor /sys/devices/platform/coretemp.0/temp3_input
sensor /sys/devices/virtual/hwmon/hwmon0/temp1_input

[ edit the file /etc/thinkfan.conf with your favourite editor, e.g. ‘sudo gedit /etc/thinkfan.conf‘ ]

5. add the following to /etc/modprobe.d/thinkfan.conf: ‘options thinkpad_acpi fan_control=1’

$ sudo sh -c ‘echo “options thinkpad_acpi fan_control=1” >> /etc/modprobe.d/thinkfan.conf’

6. reload kernel module ‘thinkpad_acpi’

$ sudo modprobe -r thinkpad_acpi
$ sudo modprobe thinkpad_acpi

7. set START=”yes” in /etc/default/thinkfan

[ edit the file /etc/default/thinkfan with your favourite editor, e.g. ‘sudo gedit /etc/default/thinkfan‘ ]

8. start thinkfan:

$ sudo /etc/init.d/thinkfan start

9. check whether it works

$ sudo cat /proc/acpi/ibm/fan

if level has a value between 0 and 7, and changes by times, your thinkfan daemon works.