Epson SureColor F7170 User Manual page 153

If the drawn line and white line are misaligned as shown in the illustration below,
proceed to Step 8. If they are aligned, proceed to Step 9.
8. While checking the state of the two lines on the front side of the printer, use the
hexagon wrench (large) to adjust the screw so that the drawn line aligns with the
position of the dotted line.
Problem Solver 153