Fan shutting off after a while

Robotics & Edge Computing Jetson & Embedded Systems Jetson Orin Nano
1

After startup. the fan pwm is set to 128.
After about 1-2 minutes, the pwm value starts rising until it hits 255, shutting the fan off.
This seems to be independent of the actual temperature.

From what i can tell, nvfancontrol is responsible for handling fan behaviour.
Content of /etc/nvfancontrol.conf (symlink to /etc/nvpower/nvfancontrol/nvfancontrol_p3767_0000.conf):

#
# Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
#
# NVIDIA CORPORATION and its licensors retain all intellectual property
# and proprietary rights in and to this software, related documentation
# and any modifications thereto.  Any use, reproduction, disclosure or
# distribution of this software and related documentation without an express
# license agreement from NVIDIA CORPORATION is strictly prohibited.
#

POLLING_INTERVAL 2

<FAN 1>
	TMARGIN ENABLED
	FAN_GOVERNOR cont {
		STEP_SIZE 10
	}
	FAN_CONTROL close_loop {
		RPM_TOLERANCE 100
	}
	FAN_PROFILE quiet {
		#TEMP 	HYST	PWM	RPM
		0	0	255	6000
		10	0	255	6000
		11	0	187	4000
		31	0	187	4000
		70	0 	0	0
		105	0 	0 	0
	}
	FAN_PROFILE cool {
		#TEMP 	HYST	PWM	RPM
		0	0	255	6000
		35	0	255	6000
		70	0 	0	0
		105	0 	0 	0
	}
	THERMAL_GROUP 0 {
		GROUP_MAX_TEMP 105
		#Thermal-Zone Coeffs Max-Temp
		CPU-therm 20,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 0
		GPU-therm 20,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 0
		SOC0-therm 20,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 0
		SOC1-therm 20,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 0
		SOC2-therm 20,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 0
	}
	FAN_DEFAULT_CONTROL close_loop
	FAN_DEFAULT_PROFILE quiet
	FAN_DEFAULT_GOVERNOR cont
	KICKSTART_PWM 64

As far as i can interpret this, fan pwm should decline as temperature rises, which sounds correct.
However, the actual behaviour is different.

3

Hi kull,

Are you using the devkit or custom board for Orin Nano?
What’s your Jetpack version in use?

Could you try to disable nvfancontrol service and check if the fan would still shut off?

$ systemctl stop nvfancontrol
4

We are using a custom board

We are using l4t 35.4.1, not sure about the jetpack version

Disabling the service right after start results in the fan speed staying at its default value, not shutting off.

5

Yes, it is expected.

Could you state what’s your current issue about fan?

6

With the nvfancontrol service, it will turn itself off eventually.
Without the service, it will just stay at the same level regardless of temperature, so either we set it to low and risk overheating, or we set it to high and waste power/make noise

If I understand correctly, nvfancontrol should set the fan speed dynamically depending on the temperature

7

It seems you would like this service enabled.

What’ your current issue when this service is enabled?
Do you mean the fan will turn off even when the temperature of the board is high?

8

yes

yes

9

Do you mean just fan turn off or the whole board?

What’s the temperature of the board at this memoent?

Please also share the full serial console log for further check.

10

The Fan shuts off a couple of minutes after startup. Just the fan, the board itself keeps running.
The temperature at this point varies of course, but my latest test showed a temperature of ~68°C.
Heating the board further afterwards does not cause the fan to restart.

I’m not sure what exactly you mean by this
The only thing I’m running on any console (ssh) is the following command to monitor pwm/temperature:

watch 'nvfancontrol -q; echo "temp: "; cat /sys/devices/virtual/thermal/thermal_zone*/temp;echo ""; echo "pwm"; cat /sys/class/hwmon/hwmon2/pwm1'

Which shows the pwm rising slowly until it hits 255, shutting the fan off.
The last relevant output of the above command is:

FAN1:FAN_PROFILE:quiet
FAN1:FAN_GOVERNOR:cont
FAN1:FAN_CONTROL:close_loop
temp: 
69031
68968
-256000
-256000
-256000
66312
66687
67656
69156

pwm
255
11

Please refer to the following instruction to capture serial console log.
Jetson Nano & NX Style - Serial Debug Console - JetsonHacks
You need to find the debug UART pin from your custom board.

How do you reproduce the issue?
(i.e. how do you increase the temperature of the board?)

12

minicom.txt (86.1 KB)
This is the serial log of the boot process. Is that what you mean?

The issue happens even if I don’t touch/heat the system.
To heat for testing purposes, I’m using a heat gun.

13

Yes, this is the log what I mean. But I want to check the log from boot up until you see the fan get stopped.

If you temperature of the board is normal, the fan would stop as expected.

Have you tried to modify this config with other value for your issue?

15

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.