Anytime you hear, “grinding” noises when your machine is printing or making copies, it indicates you have a serious problem and you need to call for service immediately. There is are many gears in a multifunctional copier or laser printer that are moving during the process of the digital image from the machine being transferred to the paper itself. When you hear a grinding noise during the printing process, this indicates that somewhere in the machine, there is a bad gear. Most of the gears in a multifunctional copier or laser printer are plastic and if the problem is allowed to go unchecked, it will destroy, damage or weaken the other gears or assemblies connected to it. That’s why it is a good idea to call for service immediately. If you are a bit familiar with your machine, a couple of simple things to check for would to make sure all the doors are securely shut. A good example would be the toner door where the toner cartridge goes in, if this door is not all the way shut but enough to trick the sensor into thinking it is totally shut, then you might get a grinding noise. The toner cartridge may be damaged, this could make a grinding noise and needs to be replaced. The more severe problems would include the fuser assembly, the swing plate gear assembly and in some cases, although rare, the main gear drive assembly.