Epson Stylus Pro 7900 - Page 315

Pro 7900 and 9900 Field Repair Guide 10/6/10
Ink Mark Sensor Position Adjustment Printer Component, Software Item, LCD Display, Printer Button Page 315.
5. Rest the Ink Mark Sensor on the Jig, and tighten 3 Screws.
1. Rest the Ink Mark Sensor on the Jig.
2. Tighten 3 Screws.