HP 2 - Manual (Page 91)

1. nozzle plate and ink nozzles 2. faces and edges of print cartridge 3. copper
contacts
Caution! Do not touch the print cartridge ink nozzles or copper
contacts. Touching these parts will result in clogs, ink failure, and
bad electrical connections.
3. Inspect the face and edges of the print cartridge for fibers.
Repeat steps 1 and 2 above if fibers are still present.
4. Repeat steps 1 through 3 for the second print cartridge.
5. Wipe the underside of the print cartridge cradle walls using clean, moistened
cotton swabs.
Repeat this process until no ink residue appears on a clean swab.