I had to open the printer to fix the power supply of the HP P1102W Laser printer that turned on at 220W and after completing the service I was cleaning the printer inside and when I tilted the printer upside down a piece of plastic fell off. Now I don't know if this part is part of the printer or if it is from another device.

What kind of error is it when the blue panel led flashes?
where can I get the HP P1102W printer service manual?

Here you are

DOWNLOAD hp laserjet p1102w service manual : HP LaserJet Pro P1102.pdf
DOWNLOAD HP P1102W :

I learned that the loose part that came out of the printer was from an old toner cartridge that accidentally dropped into the printer

Now I have to find out why the print on the leaves are coming out so faint, almost imperceptible. The power supply has been repaired but the printout is coming out very weak, almost unreadable

Have you tried checking the print on another cartridge? Throw off the test print scan