HP 1200 Service Manual - Page 139

Note Checking the toner cartridge Image formation defects are many times the result of problems in the toner cartridge. If there is any doubt, always replace the toner cartridge before troubleshooting image defects. Use the following checklist to make sure that the toner cartridge is still operable. " Make sure that the toner cartridge is seated properly. " Inspect the toner cartridge for toner level. " Check the expiration date stamped on the toner cartridge box. " Check the toner cartridge to see if it has been disassembled or refilled. " Inspect the toner cartridge to see if toner is leaking through worn seals. " Check the surface of the photosensitive drum in the cartridge to see if it has been damaged or scratched. Touching the drum contaminates the photosensitive surface and can cause spotting and image defects. " Blurred areas on printed pages indicate that the photosensitive drum in the cartridge has been overexposed to light. Because overexposure to light causes permanent damage to the photosensitive drum, the cartridge should be replaced. A toner cartridge weighs approximately 863 grams (30.5 oz) when it is full, approximately 766 grams (27.0 oz) when it first fades, and approximately 742 grams (26.2 oz) when it is empty. To redistribute toner in the cartridge Before installing a new cartridge or when toner begins to run low, redistribute the toner by rotating the cartridge back and forth five or six times. EN Errors 137