HP Color LaserJet 8550 Multifunction Printer series - Manual (Page 287)

EN
Replacing toner cartridges 287
Replacing toner cartridges
When a specific toner cartridge begins to run low, the
** (COLOR)
TONER NEEDS TO BE REPLACED
message appears on the copy
module touch panel display. The copy module can continue making
copies even when this message appears.
Note Gently rocking the toner cartridge back and forth several times and
placing it back into its original position may cancel the toner message
temporarily.
Figure 57 Toner cartridge message -
** (COLOR) TONER NEEDS TO BE
REPLACED