The question seems to have a misunderstanding. It's important to note that one printer cannot both change cartridges and add toner.
Printers are generally divided into three main categories: dot matrix printers, inkjet printers, and laser printers. Each category uses a different print medium.
Dot matrix printers use ribbons as their print medium. The internal composition of the print head consists of various steel needles. If the printing effect appears shallow, it typically indicates that the ribbon needs to be replaced. If there are broken lines or other effects, it's likely that a needle is broken and needs to be replaced.
Inkjet printers use ink cartridges as their print medium. Ink cartridges are simply composed of ink tanks and printheads. Some inkjet printers have separate ink tanks and printheads. Those in which the ink tank and printhead are combined are called one-piece cartridges, while the ones that are separate are referred to as the ink cartridge and the printhead.
When an inkjet printer's printing effect starts to fade or when the picture's color appears abnormal, it's mostly due to ink depletion or clogging. Most printers will typically indicate when they are low on ink. In such a case, users often choose to add ink to extend the life of the consumables. However, the added ink is usually only compatible ink, and its quality is not stable. Therefore, the resulting effect may not be very good. If you need good results, it is best to replace the ink cartridges.
Finally, laser printers use toner cartridges. Similar to inkjet printers, toner cartridges can be either integrated or separate. If the drum and toner are integrated, it is referred to as an integrated cartridge. If they are separate, they can be called drum assembly and powder assembly.
When the printed results appear normal on the sides but light in the center, it often indicates that there is no toner left. In this case, it's time to add toner.
I hope this clears up any confusion.
