HP 220240 - Manual (Page 64)

2.12 Printing the Engine Test Print
The Engine Test Print (Figure 2–4) is used to check the printer’s paper
feed mechanism for proper operation, and to check toner dispersion and
line weight.
The area between the lines on the Engine Test Print should be free of excess
toner or smudges, and the lines should print cleanly across the entire page
with no faded areas. If the print quality is poor, see Section 6.6 for help to
correct the problem.
If the Engine Test Print will not print, there may be a problem with the
paper feed mechanism. Refer to Section 6.6 for help to correct the problem.
If you cannot correct the problem, call Digital Services to repair the printer
(see Chapter 8 for service information).
You can check line weight by looking at the thickness of the line after
performing a print density adjustment (Section 2.11).
Operating Information 2–37