To maintain print quality over the entire life of the cartridge your machine automatically adjusts to compensate for changes in the electro-characteristics of the toner powder. These changes are caused by the electrical charging and discharging process, and eventually mean that your machine can no longer maintain optimum print quality. When this happens the toner cartridge must be replaced.
Your machine can therefore indicate "Toner Life End" or "Replace Toner" for either of these reasons:
- The toner cartridge is empty (the machine uses light beams to detect an empty toner reservoir)
- The quality of the toner powder has deteriorated below the level needed for optimum print quality (the machine uses a roller counter to determine the number of times the toner powder has been electrically charged and discharged)
This can happen for all color toner cartridges at the same time.