When I restarted after shutting down once, I found that it could not be turned on. After long pressing S4, only CR5 lights up in red, and then goes out after a while, other LED lights are not lit.What’s the reason？
CR5 just indicates power is present. Other LEDs would depend on the system booting (or starting to boot). If power is connected, then CR5 should stay on.
Do you have serial console available? A log from this would be the best bet, but if you want a very basic test, run “
dmesg --follow” on the host PC, then attach the provided micro-B USB cable to the host PC, noting if you see any logs produced from the USB insert. Then try to put the system in recovery mode, and see if there are any logs from that (hold the recovery button down, and then add power or tap the power on button if power is already connected…no need to hold buttons down after power is applied or the power button is tapped). Recovery mode has very little requirement, and so as the micro-USB goes into device mode for recovery the host PC should see this.