If you’re running a Raspberry Pi, you may occasionally see a flashing icon of a red, half-full thermometer in the upper right corner of the currently running application’s screen. We noticed the red thermometer icon appear in Kodi for example. This is an indication that your Raspberry Pi CPU temperature may be running high or has surpassed the soft temperature limit as defined in config.txt. You can of course change the soft limit by editing config.txt to a higher or lower value as needed. With this said, you may also need to manually check the CPU temperature or monitor it if you have some high intensity processes running on your Raspberry Pi.
How to check CPU/GPU Temperature on Raspberry Pi
When you login to your Raspberry Pi from the command line, the motd will show you a snapshot of your Pi’s current CPU/GPU temperature. To check the temperature of your Raspberry Pi‘s CPU manually, you can use “measure_temp” like this and it will display the current temperature:
pi@retropie:~ $ /opt/vc/bin/vcgencmd measure_temp
temp=39.2'C
Take this one step further and use the Linux command ‘watch’ to monitor your CPU temperature in realtime, or every 2 seconds if you’re just running command without options. For example:
Every 2.0s: /opt/vc/bin/vcgencmd measure_temp retropie: Sat Aug 23 09:32:00 2020
temp=38.6'C
Changing the default temperature limit in config.txt
You can of course change the default temperature limit by adding or changing the following config key in config.txt which can be found in /boot/config.txt
temp_limit=85
This is a fairly simple solution for something that we rarely need to check, but when we do, we’ve often forgotten how to do it. Enjoy.