How do I turn off the jetson orin nx Fan Transfer service

[whjshishen]

My system version is jetpack 6.2, after I set the fan pwm to 255, it will automatically reduce, but I can’t find the service that automatically controls the fan speed, please tell me how to turn it off

[KevinFFF]

Hi whjshishen,

Please run the following command before you control FAN pwm to 255 to prevent nvfancontrol.service reduce the fan speed.

$ systemctl stop nvfancontrol
$ systemctl status nvfancontrol.service

[whjshishen]

Thank you for your reply. After I tried, I found that the fan still automatically sets the speed, and I checked that the nvfancontrol service is off. Is there anything else that might cause this problem?

[KevinFFF]

We can not reproduce this behavior on the devkit.

Are you using the devkit or custom board for Orin NX?

Please share the result of the following command on your board.

$ cat /etc/nv_tegra_release
$ cat /etc/nv_boot_control.conf
$ systemctl list-units --type=service | grep fan

[whjshishen]

Both jetson orin devkit and orin nx modules have this problem when using jetpack 6.2. Here are the results of running commands with the jetson orin devkit.I think it is because of the jetpack version. I have used jetpack 5.1 before without this problem

[KevinFFF]

Currently, it seems kernel would take control when nvfancontrol is stopped.

Please run the following command to check if it could help in Jetpack 6.2.

# systemctl stop nvfancontrol
# grep "" /sys/class/thermal/thermal_zone*/type|grep tj-thermal
/sys/class/thermal/thermal_zone8/type:tj-thermal
(check which thermal zone with type:tjthermal, it is thermal_zone8 in my case)
# tee /sys/class/thermal/thermal_zone8/policy <<< user_space
# echo 255 > /sys/devices/platform/pwm-fan/hwmon/hwmon0/pwm1

You may restore it with the following command:

# systemctl restart nvfancontrol

[whjshishen]

hi, according to your instruction, now my fan will not be affected by temperature and can run at full speed by manual control. May I ask why it did not work before? Thank you for your help

[KevinFFF]

@whjshishen

May I ask why it did not work before?

We add new feature in JP6.x that kernel would take control for FAN once the nvfancontrol service is stopped so that you also have to configure the policy to user_space.

[whjshishen]

OK, thanks, and have a great weekend