HP Color LaserJet 5550 Printer series - Manual (Page 157)

3. Grasp the green handles on the transfer unit and pull down.
4. Remove the cyan print cartridge from the printer.
CAUTION Do not place the cyan print cartridge on the transfer unit while it is open. If the transfer unit is
damaged, severe print quality problems may result.
5. Remove the OHT sensor cleaning brush from the base of the printer.
6. Insert the brush into the base notch and brush from right to left four or five times.
CAUTION Do not brush back and forth over the sensor. This will smear dust over the sensor and cause
printer errors.
7. Replace the OHT sensor cleaning brush into the base of the printer.
8. Align the cyan print cartridge with the tracks inside the printer and insert the cartridge
until it is completely seated.
ENWW Periodic cleaning 143