Printer Faults - Black Pages

Totally black pages usually signify something horrible wrong with the precharge and developer voltages so that the photoconductor is not working properly and is simply stripping all the toner available from the developer.

The fault often looks dramatic, with the page being heavily overladen with toner. The toner moved may exceed the paper's capacity and dump toner into the paper path. The actual fault may be nothing more than a bad connection.

If the printer seems to work properly but gives an ordinary looking but totally black page the fault may be a failed laser or blocked laser path (if it's write white). Alternatively the optical path isn't working properly - something is obstructing it.

If cleaning and checking connectors doesn't work it may be necessary to measure the transfer voltages. This is not an easy job. Most ordinary meters have a limit at 600 Volts and the voltages used in laser printers can easily exceed 1,000 Volts so a high voltage probe and the skill to use it are needed.