Brother International HL-3400CN Service Manual - Page 305

HL-3400CN SERVICE MANUAL 1-1 Background Phenomenon Background is smeared due to toner spread as shown in print sample (1) of Page 8-45. Main Causes (1) Too small toner mass and charging level in the developing process. (2) Poor contact of the developer roller's bias pole. (3) Life expired or failure of the OPC belt cartridge. (4) Failure of the high-voltage power supply unit. Countermeasures (1) Replace the toner cartridge. (2) Confirm if the developer bias pole is deformed or not. (3) Replace the OPC belt cartridge. (4) Replace the high-voltage power supply unit. 1-2 Missing Image at Edge Phenomenon There is missing or peeling toner found in the image at the edge as shown in the print sample (2) of Page 8-45. Main Causes (1) Too small toner mass and charging level in the developing process. (2) The OPC belt is deformed (waving). Countermeasures (1) Replace the toner cartridge with a new one. (2) Replace the OPC belt cartridge with a new one.