HP 4550 Service Manual - Page 88

1 Replacing the toner cartridges Replace the toner cartridge when the control panel displays: TONER CMYK OUT. The display can indicate that one or more toner colors are out. 1 With the printer turned on and warmed up, push the dark gray release button on the side of the printer ([1]) and open the printer's top cover ([2]). 2 Note If you need to replace a toner cartridge and the TONER CMYK LOW or TONER CMYK OUT messages are not displayed on the control panel, open and close the top cover. Wait for the PRESS SELECT TO CHANGE TONER message to appear on the control panel. Press [SELECT] and the message TONER=(COLOR) appears on the printer control panel. Press [-VALUE+] to select the toner cartridge you want to replace, and proceed to the following steps. 3 2 Lift the toner access cover and remove the used toner cartridge. CAUTION Do not shake the toner cartridges after removing them. 3 Position the toner cartridge over the cartridge slot so that the blue arrow on the toner cartridge points to the blue arrow on the printer. The arrow on the right (control panel side of the printer) should point straight down. 86 Printer maintenance C7085-90921