Printer boot in loop

[moti30]

Hi.
I have a Xerox B215 printer.
The problem with the printer is that every time I plug it in, it starts up for about half a minute, and then reboots in a loop.
The problem happens even when the toner is out of the printer, even when I disconnected all the cables from the motherboard, except for the voltage cable that comes from the transformer board.
Apparently the problem is with the motherboard, there is probably some component there that disconnects the power, which causes a reboot.
I can't check if the problem is with the firmware, since I don't know how to install firmware when the printer is unplugged (and when the power is plugged in, it doesn't boot properly).

Does anyone have any ideas (besides replacing a motherboard, which is expensive)?

This is how it looks

 

[rjenkinsgb]

Try this, from a support forum?? It should reset the internal parameters so it starts as new again, by the look of it:

Power off the device. Press and hold home and then power button down. This will take you to boot options. At the top of the screen you will see special boot menu press and hold s,b and t and press home. Password 6789#. Try initialize nvram. You can try each one if you don't mind having to reset the printer to factory settings. ( I'm a printer tech).

https://www.reddit.com/r/Xerox/comments/x8e7wa/xerox_b215_screen_problems

 

[moti30]

Pressing the home button with power button brings me to the calibration screen.
The printer also reboots in the calibration screen.

 

[augustinetez]

More likely a power supply fault (as in faulty capacitors) rather than corrupted firmware.

 

[moti30]

I checked the main (large) capacitor of the power supply with a multimeter (while still attached to the board).
In the resistance test the value was 1, and in the voltage test there was capacity in the capacitor (when the voltage was connected it was about 700V capacity).
The other small capacitors, I did not see an external defect in them, and I have not tested them for now.

 

[aliarifat794]

Inspect the motherboard carefully for any signs of physical damage, such as burnt components, bulging capacitors, or loose connections.

 

[rjenkinsgb]

The other small capacitors, I did not see an external defect in them, and I have not tested them for now.

The only way to test the caps properly is with an ESR meter.