HP Latex 3000 Printer - Manual (Page 241)

TIP: Remember which printhead came from which slot; the printer will report an error if you later
replace a printhead in the wrong slot.
2. Illuminate the printhead slot in the carriage and check the electrical connections to the printhead for
dirt.
TIP: Placing some white paper behind the electrical connections will improve contrast and may help
you to check for dirt.
3. Clean the dirty connections gently but thoroughly using the brush provided in the HP Latex 3000 Printer
Cleaning Kit. A piece of paper or cloth can be used to collect the dirt.
ENWW Clean the printhead contacts 235