Our Raspberry Pi 3 became disconnected from resin.io and was completely inaccessible. When we got physical access to the device the red power light was constantly illuminated and the green light was flashing 4 times in a row. We are running Resin OS 2.12.5+rev2 so are on a fairly recent operating system.
Having looked at the Raspberry Pi troubleshooting pages I found that on the original Raspberry Pi bootloader this means that start.elf was not launched. Power cycling the device solved the issue so I don’t this was caused by a corrupted SD card.
What would be the best steps to debug this issue? Are there device level logs available that the root cause of the crash could be identified? I hope someone has solved a similar issue or knows where is a good place to start investigating the problem.