Printhead Adjustment Adjust the Printhead Once you have printed the Check Printhead pattern, you can use it to adjust the Printhead as follows: 1 Locate the mechanical adjustment pattern in the Check Printhead pattern. 2 Using a Measuring Loupe, you must first measure the deviation of the Printhead in the vertical position. Deviation 3 Loosen the front screw that secures the Printhead to the Carriage Base Plate. HP Designjet 9000s Series Printer Service Manual 3-15