Printer Faults - Dark Pages

Bad connection or failure of one of the print cartridge voltages. Could be a voltage too high on the developer or too low on the drum.

Beware! if the page is heavily caked the inside of the printer is probably a horrible mess. Cleaning the printer will need to be a priority before it will work properly and that is an opportunity to check the connections.

Failed or blocked laser path (in the less usual, write white systems where the laser clears down the voltage). The page should simply be black because if the laser is down all the transfer voltages will be OK.

Dislodged or incorrectly set doctor blade in the print cartridge. Print areas will be heavily caked but because there is so much toner it darkens other areas as well.

Dislodged or damaged waste toner cleaning blade - the pages will quickly build up a dirty then a black background.

It may be necessary to measure the transfer voltages.