Fan Speed Control Issues on Jetson Orin Nano

Issue Overview

Users of the Nvidia Jetson Orin Nano Developer Kit are experiencing problems with fan speed control. The main symptoms include:

• Fan not working continuously, only running for 1-2 seconds and then turning off for 4-5 seconds
• Fan speed not reaching maximum when running
• Board overheating, with temperature warnings being displayed
• Attempts to modify /etc/nvfancontrol.conf not resolving the issue
• High CPU temperatures (around 82°C) reported by tegrastats

The problem occurs during normal operation of the board and significantly impacts system cooling and performance.

Possible Causes

1. Conflicting fan control processes: Multiple fan control scripts or services running simultaneously, interfering with each other.
2. Incorrect configuration in /etc/nvfancontrol.conf: The fan profile settings may not be properly adjusted for the specific use case or ambient conditions.
3. Hardware issues: Faulty fan or connection problems between the fan and the board.
4. Software bugs: Issues with the nvfancontrol service or other system components responsible for fan control.
5. Environmental factors: Inadequate overall cooling or high ambient temperature in the operating environment.

Troubleshooting Steps, Solutions & Fixes

1. Check for conflicting fan control processes:
   Run the following command to identify any fan-related processes:

   ps aux | grep -i fan
   

   If you see multiple processes (like nvfancontrol and custom scripts), disable or remove the unnecessary ones.

2. Disable custom fan control scripts:
   If you have any custom fan control scripts (e.g., fan_control.py), disable them:

   sudo systemctl stop <your_custom_fan_service>
   sudo systemctl disable <your_custom_fan_service>
   

3. Verify nvfancontrol service status:
   Check if the nvfancontrol service is running correctly:

   sudo systemctl status nvfancontrol
   

   If it’s not running or showing errors, restart it:

   sudo systemctl restart nvfancontrol
   

4. Modify /etc/nvfancontrol.conf:
   Edit the file with more aggressive fan control settings:

   sudo nano /etc/nvfancontrol.conf
   

   Use the following profile as a starting point:

   FAN_PROFILE cool {
       #TEMP   HYST    PWM     RPM
       0       0       128     3000  # 50% speed at 0°C
       30      0       192     4500  # 75% speed at 30°C
       60      0       255     6000  # Max fan speed at 60°C and above
       105     0       255     6000
   }
   

   After modifying, restart the nvfancontrol service:

   sudo systemctl restart nvfancontrol
   

5. Test maximum fan speed:
   Force the fan to run at maximum speed to check if it’s functioning correctly:

   echo 255 | sudo tee /sys/devices/pwm-fan/target_pwm
   

   Check the fan RPM:

   cat /sys/class/hwmon/hwmon0/rpm
   

   A properly functioning fan should show a high RPM value (around 6000).

6. Monitor temperatures:
   Use tegrastats to monitor temperatures while running demanding tasks:

   tegrastats
   

   If temperatures remain high even with the fan at maximum speed, consider improving overall system cooling.

7. Check for hardware issues:

   • Ensure the fan is properly connected to the board
   • Inspect the fan for any physical damage or obstruction
   • If possible, try a known working fan to rule out hardware failure

8. Update Jetson software:
   Ensure you’re running the latest JetPack version, as it may include fan control improvements:

   sudo apt update
   sudo apt upgrade
   

9. If issues persist, consider resetting the entire fan control configuration:

   sudo cp /etc/nvfancontrol.conf.default /etc/nvfancontrol.conf
   sudo systemctl restart nvfancontrol
   

10. For advanced users, consider implementing a custom fan control solution using the PWM interface if the default nvfancontrol doesn’t meet your needs.

If these steps don’t resolve the issue, it may indicate a more serious hardware problem or a bug in the Jetson software. In this case, contacting NVIDIA support or consulting with the Jetson developer community for further assistance is recommended.