HP Designjet 4500 Printer series - Manual (Page 193)

3. When the carriage has stopped moving, the front panel will ask you to open the window.
4. Locate the carriage.
5. Pull up and release the latch on top of the carriage.
6. Lift up the cover. This will now give you access to the printheads.
ENWW Remove a printhead 179
How do I... (ink system
topics)