OnOff Shim turns Pi off but will not turn Pi On

Support
1

Hello,

I hope you are well. Please could some of the wise on this group assist me. I’ve got no more hair to pull out. I have tried reading various forums and chatgpt to no avail.

Issue

I am trying to install an OnOff Shim (shop.pimoroni.com). it works to switch the Pi off. However, it does not work to switch on Pi.

when i hold the switch on the shim, the LED on the shim turns on (red), and the LEDs on the Pi begin to flash to indicate the Pi is receiving power.

However, as soon as i release the button on the shim, the red light on the shim goes off and the lights on the pi switch off (and the pi does not boot/turns off).

What is supposed to happen

After releasing the button on the shim, the pi boots and stays on.

What have i tried so far

if i plug the power into the pi then i can boot and pi works normally. If i then connect onoff shim after boot, i can use the onoff shim button to power off, this works ok.

I have tried holding the pi on for 10-15 seconds, but this makes no difference.

I have tried a different power supplies and cables

I have also tried two different OnOff shims and get the same result. I have tried 3 different Pis, Zero, Zero 2 W and 2B and get the same result.

I have tried a few edits of the overlays in /boot/config.text , but these have not proved sucessful.

tried to follow this forum, but cannot actually see what the solution was, and if relevent to mee, as i use the default pins. OnOff Shim wont stay on - Support - Pimoroni Buccaneers

debug information

I’m using default pinout ( not tried to change anything)

soldering should be good ( tested with a multi-meter, and in my frustration order a second onOff Shim and tried again just in case)

power is connected to the shim (not directly to the pi).

OS: Raspberry Pi Lite (Debian 11.11 (Bullseye)

installed via the standard curl command

~ $ raspi-gpio get 4

GPIO 4: level=1 fsel=0 func=INPUT

~ $ raspi-gpio get 17

GPIO 17: level=1 fsel=0 func=INPUT

/boot/config.txt

the only overlay is :

dtoverlay=vc4-kms-v3d

/etc/cleanshutd.config

#daemon_active=1

trigger_pin=17

led_pin=17

poweroff_pin=4

hold_time=1

shutdown_delay=0

polling_rate=1

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2

Have you already tried to turn the Pi on with a short press of the button? That should be the normal mode of operation.

In addition, do you use any hats? Probably not, but just to be sure. You could also post an image of your soldering.

3

Hi ,

Thanks for the prompt response. I have tried short press to no available. The green light on the pi flicked for a second after I released the button. But ultimately pi did not boot and the LED switched off.

No phats. 1-wire is not enabled.

Kernal is 6.1.21-v7+.

Original post edited to include images

4

Hm, I think you soldered the connector to the wrong side:

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5

I’ve just desoldered and cleaned up using isop alcohol as I noticed I had a short between 5v and gnd.

Tried to test again without soldering, but then saw a small flame. So looks like I’m shorting again.

Can anyone advice what I’ve done wrong. Note that I’ve unusually used a female header then jumper wires as my pi has female headers.

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6

No idea. The wiring looks correct now, but any shorts caused by soldering are not visible. And if you saw a flame, it could very well be that something did not survive the smoke test.