Raspberry Pi 4 Model B Rev 1.4 8GB fanshim never stops

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1

I’ve installed a fanshim on a Raspberry Pi 4 8GB, and the fan never goes off. The service script runs fine. LED can be switched, but the fan can’t be switched off. I’ve checked/bended the pins. I’ve tried with a second fanshim. No luck.

Might there be a problem with the new Rpi 4 8GB? The same fanshim works well on a Rpi 4 4GB.

2

You could try editing config.txt file
sudo nano /boot/config.txt
and adding this line.
dtoverlay=gpio-fan,gpiopin=18,temp=55000
The fan should then turn on at 55c.
If the fan works its a software issue with the Pimoroni Daemon.
If it still doesn’t work you have more sleuthing to do.

3

Thanks for the fast reply. The command works well on the 4GB model, but not on the 8GB model. :-(

kernel: 4.19.118-v7l+ #1311 SMP Mon Apr 27 14:26:42 BST 2020 armv7l GNU/Linux
pimoroni fanshim: git id c8ea18b9 (latest on master)

4

Kind of sounds like you have a hardware issue with that Pi 4B?
If you want to disable the fan shim service while trying other things its
sudo systemctl stop pimoroni-fanshim.service
sudo systemctl disable pimoroni-fanshim.service

Before doing that try fanshim.set_fan(True)
from here https://github.com/pimoroni/fanshim-python

Turn the fan on with:
fanshim.set_fan(True)

Turn it off with:
fanshim.set_fan(False)

You can also toggle the fan with:
fanshim.toggle_fan()

You can check the status of the fan with:
fanshim.get_fan() # returns 1 for ‘on’, 0 for ‘off’

To enable the fan shim service again it’s
sudo systemctl enable pimoroni-fanshim.service
sudo systemctl start pimoroni-fanshim.service

5

All those commands work, event the LED lights turns blue. But the fan is running and running and running…

>>> from fanshim import FanShim
>>> fanshim = FanShim()
>>> fanshim.set_fan(False)
False
>>> fanshim.toggle_fan()
True
>>> fanshim.get_fan()
1
>>> fanshim.toggle_fan()
False
>>> fanshim.get_fan()
0
>>> fanshim.set_light(0, 0, 255)
6

The way it works is the fan control pin is pulled low to turn the fan off. It’s a fail safe I guess, with no software installed the fan will just run continuously as that pin will be floating (not grounded). If the fan shim isn’t making contact with that control pin the fan will never shut off.
The only other thing I can think of is to disable the service and then use gpio zero or some other utility to set that pin low (ground). If the hardware on the Pi is working OK, the fan should stop.

7

if it not soldered to the pins ,try putting another hat on top or just a header if you have one to hold it tight , i also have used a q-tip just cut the tips off .and bush it down between the row of pins

8

I was the hardware. The solderless fanshim didn’t contact the pins.