OnOff SHIM on Pi3B+ using toggle-switch

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I received my OnOff SHIM today and installed it on my Pi3B+. It works flawlessly using the included push-button or an arcade-button attached to the breakout-pins.

BUT :-)
I would love to use one of these toggle-switches. The LED-feature is optional. I tested if they would work by just crossing 2 jumperwires attached to the button-breakout-pins. Result: the Pi boots but keeps hanging on some point. I can’t see anything valuable in the logs. Any ideas for this?

I also found this guy on YouTube who seems have it working using a different toggle-button.

Thanks for your help…

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The button on the on off shim, and arcade buttons are “momentary contact switches”. The contacts are shorted when the button is pressed and only while the button is pressed. Take your finger off and its an open circuit again.
Latching toggle switches toggle between being always on or always off. Move the handle one way and the contacts are shorted and stay shorted as long as the handle in in that position. Switch it the other way and they are open circuits and stay open circuits until the handle is moved again.
You can get momentary contact toggle switches. It’s like the arcade button but with a handle instead of the button. The handle moves but doesn’t latch in position. When you take your finger off it springs back to its original position.
The on off shim wants to see a momentary switch, not a latching switch.
Short press for on, long press for off etc. Using a latching switch does one very long press and likely messes it up. Try turning your toggle switch on, then quickly turn it off again. You should get your normal boot up. On for 1 second and off again should work. On for more than a second and off again should do a shutdown.

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Thank you for this reply. But can you state WHY exactly it doesn’t work using a permament closed circuit for switching on? Is it a software or a hardware-limitation?

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It’s probably both. I didn’t build it so I can’t say exactly what’s going on. All I can tell you is, if you want to use that switch your going to have to switch it on and off again. Or use the correct switch.

EDIT: Boot up is hardware only, as near as I can tell. Shutdown is hardware and software.