Raspberry Pi 4 doesn't boot after shutdown unless I wait

[sodki]

Hi,

I have a Raspberry Pi that boots and works fine, but if I shut it down via any method it won't boot again until I wait some time. I usually wait one hour and it works. I don't touch any cables or do any re-plugging of any component, only the power connection at the socket. When I try to boot it before waiting the red LED stays on and the green LED quickly blinks two or three times and then stays off.

Any ideas?

[neilgl]

What power supply are you using for it?

[sodki]

The official one from Raspberry Pi.

[pcmanbob]

So once you have shutdown your pi and switched the power off at the mains socket,

What does the red LED Do ?

If you wait for it to go out then you should be able to power the pi again and it should boot normally.

[sodki]

Once I shutdown safely and switch the power off at the mains socket, the red LED turns off. If I then turn the mains back on, the Raspberry Pi won't boot.

If I wait a while before turning the mains back on, then it will boot. I know that if I wait 1 hours it will boot, I know that if I wait 5 minutes it won't boot. I need to do more tests to know exactly how much time I need to wait, for my own sake as well.

I initially though that it could be due to some thermal issue, but I can replicate this even if the Raspberry Pi has been off all night.

[pcmanbob]

So what happens if you pull the power cable out of the pi once its shutdown instead of turning it off at the mains,

or alternatively what happens if you pull the power supply out of the mains after its turned off ?

[sodki]

It's the same thing if I unplug at the mains or disconnect the power cable from the Raspberry Pi.

[pcmanbob]

Sorry but I just don't see what could cause this removing all power from the pi should just result in a clean boot once power is returned.

I can shutdown both my pi4's waiting for the green LED to stop flashing , pull the power cable from the pi, count to ten ( 10 seconds ) reconnect the power cable and the pi will boot back up without any problem, I don't even need to turn the power off at the mains.

[davidcoton]

Do you have powered peripherals connected? Have you tried without them?

[sodki]

I only have keyboard and mouse connected, doesn't make a difference if I have them plugged in or not.

Also this behaviour doesn't show up on reboot, only shutdown.

[pcmanbob]

Clutching at straws now, but try this and lets see if anything changes.

shutdown pi as you normally would , making sure green LED has stopped flashing .

remove power , by what ever means you want

once red and green LED's are off wait 10 seconds

remove SD card

apply power to pi , do you get the red LED on and the green LED flashing 4 time then a break then repeating 4 flashes ?

remove power , by what ever means you want

once red and green LED's are off wait 10 seconds

insert SD card

apply power to pi, does it boot correctly ?

[sodki]

Without the SD card the Raspberry Pi's green led shows the pattern you described. It does not boot after following your instructions.

[pcmanbob]

Then at the moment I don't have any idea why you I will not boot after being shutdown.

The only thing left would be to try flashing a fresh copy of raspbian on to another SD card and try with that.