CentOS laptop temperature sensor
Fan error on boot
Today my ThinkPad X61 failed to boot. As the system came up, “Fan error” appeared in the upper left corner of the display, and then the machine shut itself off. It will boot if I press “Esc” at that time.
Package “lm_sensors”
I was worried about overheating, so I searched for a way to monitor temperatures. This package seems to work:
lm_sensors.i686 : Hardware monitoring tools
I installed it and then ran “sudo sensors” on the command line.
The command showed some errors on STDERR, probably because there are
no sensors for some measurements. Temperautres were okay, but the
machine was still cool. It showed Fan 2 not running (0 RPM), which
is bad news.
Fan connections
Following instructions in the X61 Hardware Maintenance Manual, I pulled out the battery and removed the keyboard. Fan 2 sits in the upper left corner as you look at the display. I traced the cables and tightened two screws a little.
With the keyboard still attached to the motherboard, I put in the battery and started the X61. Then fan began to spin, then stopped, and the machine booted with no error messages. I shut it down, replaced the keyboard, and booted again. No errors appeared.
Temperature monitoring
I ran “sudo sensors” on the command line again. This time it
showed both fans running, and temperatures looked good. Now, after
running several hours, installing some updates, and doing other
normal work the STDOUT looks like this:
acpitz-virtual-0
Adapter: Virtual device
temp1: +47.0°C (crit = +127.0°C)
temp2: +39.0°C (crit = +99.0°C)
thinkpad-isa-0000
Adapter: ISA adapter
fan1: 3414 RPM
fan2: 7449 RPM
temp1: +47.0°C
temp2: +46.0°C
temp3: +46.0°C
temp4: +42.0°C
temp5: +32.0°C
temp6: +50.0°C
temp7: +30.0°C
temp8: +32.0°C
temp9: +46.0°C
temp10: +40.0°C
temp11: +0.0°C
temp12: +0.0°C
temp13: +0.0°C
temp14: +0.0°C
temp15: +0.0°C
temp16: +0.0°C
coretemp-isa-0000
Adapter: ISA adapter
Core 0: +43.0°C (high = +105.0°C, crit = +105.0°C)
Core 1: +44.0°C (high = +105.0°C, crit = +105.0°C)
Those temperatures look okay,
END