RPie reboots when switching roomlights on/off

[Frühstück]

Hey Everyone!

My MagicMirror shows strange behavior since Minute one. When a Light somewhere in our Apartment is switched on or off there is a chance that the Raspberry Pi 3B+ does a reboot. Happens approx one out of three times.

Hardware:

• Raspberry Pi 3B+ with
• PIR motion sensor and
• Raspberry Camera
• a 27" Monitor (via HDMI)
• a “main power switch” inside the case
• a charger for the RPi

I thought, the Monitor could give some bad electricity spike to the RPi and switched over to an VGA Cable but that did not help. I’ve also tried a bowerbank instead of a charger with no luck.

Sadly I can’t find any helpful links on google as the keywords “switch, light, reboot” are often used for other projects.

I am happy for any advice, thought and idea you may come up! : )

Greets,
Michael

[AxLed]

@Frühstück
I had a similar problem with a button connected to the GPIO Pins. In my case the button/pi/gpio reacted if i switched on a roomlight (which has nothing to do with my pi), even nothing was pressed at the pi.
I think the cause of your problem could be the “main power switch” of your pi case. Is this connected to the gpio pins and was there a script which was delivered with the case?
A helpful search string for google could be “interference raspberry pi gpio”.

In my case some capacitors at the gpio wiring was the solution.

AxLED

[Frühstück]

Thank you @AxLed !

I forgott to mention a power & a reboot button attached to the GPIO Pins and exactly that (false positive reboot-script execution) was the root of the Problem. I solved it with rechecking the pins for LOW-state after a 1/10 of a second.

This issue bugged me for several months. Thank you again!