HP Designjet 4500 Printer series - Manual (Page 196)

3. Push down as indicated by the arrow shown below.
When installing the new printhead there may be some resistance, so you need to press it down
firmly but smoothly.
If you have difficulty, see I cannot insert a printhead.
4. Insert any other printheads that need to be installed, and close the carriage cover.
When all the printheads have been inserted correctly and accepted by the printer, the printer will
beep.
NOTE If the printer does not beep when you insert the printhead and the Replace
message appears on the front panel, the printhead may need to be reseated.
182 Chapter 11 How do I... (ink system topics) ENWW
How do
I... (ink system topics)