How to identify mb heat sensor for R51

[abuhannibal]

I need to replace or short out a failed heat sensor so the fan will run - can anyone tell me how to find it on the motherboard? Thanks!

[lead_org Microsoft MVP Contributor]

there is no schematic for the heat sensors for the R51, but you could look at the heat sensor position on the T4x, to get a rough idea of where it is on the R51.

http://www.thinkwiki.org/wiki/Thermal_sensors#ThinkPad_R51

Unfortunately there is a glitch on the Lenovo forum, where i can't access at your post history. So what made you determine that the sensors on the R51 has shorted out?

Use TPfancontrol to manually control the fan speed, this is a far easier way to manage your heat sensor problem.

[abuhannibal]

Firstly, many thanks for the quick reply!! The fan functions, however, it is not being kicked into high speed when CPU use gets heavy, thus leading to heat-induced shutdowns. So I think that sensor is not sorted but is not functioning correctly, and surmised that the easiest way to deal with this might be to just short the appropriate leads on the sensor in order to make the fan run at full speed all the time. But any advice is appreciated.

                       -- Bob

[abuhannibal]

Correction: "sensor is not sorted" should be "sensor is not shorted"

[lead_org Microsoft MVP Contributor]

just download Tpfancontrol and leave the fan running at either level 6 or 7.

Also, what is the temperature reading for your CPU and GPU when in the Tpfancontrol?

Fan not running at full speed is usually due to the software thermal management issue, not thermocouple per se. Unless you are getting erraneous temperature reading.

It is advisable that you don't short circuit anything on the motherboard. As this may cause more damages to the motherboard. 

[abuhannibal]

Forgot to mention, machine runs Unix. it's not my machine but I will find out which version...

[abuhannibal]

Machine runs FreeBSD.

[ajkula66 Guru]

Check if any of this might work for you, my knowledge of FreeBSD is non-existant...

http://www.thinkwiki.org/wiki/How_to_control_fan_speed

http://www.thinkwiki.org/wiki/ACPI_fan_control_script

http://www.thinkwiki.org/wiki/Talk:ACPI_fan_control_script

Good luck.

[abuhannibal]

George - many thanks, will check and report back!