Printer halted! Psu dead? My Anet A8 Plus worked normally, but after the weekend and changing for new bearings on the rods, it is not working anymore at all.
I experience random reboots, the nozzle can only heat to about 10 °C away from the target and then starts to drop, the printer gives the halted error.
Example: Target is 240 °C, the nozzle temperature goes to like 232 °C and then starts to drop pretty fast. The Bed heats good otherwise.
troubleshooting so far
The PSU gives 24 V and the supply voltage switch is 220 V like it should. No matter if I try print it through OctoPrint or Cura, the same thing happens.
How it can break this bad just from replacing a few bearings is not clear to me. Do these reboots mean the PSU is dead and not giving constant voltage? Reboots come even idle or just bed heating etc.
Reboots happen in 2 cases on a printer:

If the board power has been below a the operational threshold (~3 V) and the capacitors on the board are empty, the power dip can result in a reboot.
If a device connects to the serial-USB port, it reboots.

If you power up the printer not connected to any other device, it should run continuously. If it flickers and reboots, the power-lines to the board or the PSU are bad. Check those in reverse.
If it only reboots again and again when connected to a serial port (PC, Octoprint etc), your problem is the cable - it might be jiggling or be defective, or otherwise de- and re-connect again and again.