Sensor Trimmer Adjustment - Epson Stylus Pro 9000 - Print Engine Service Manual

EPSON Stylus Pro 9000

SENSOR TRIMMER ADJUSTMENT

After replacing the C277MAIN board, you need to adjust the sensitivity of three
sensors: Paper Edge Sensor, Front Paper Sensor, and Rear Paper Sensor.
You also need to perform this adjustment if you replace one or more of these
sensors (perform the adjustment only for the sensors that you replace).
To perform the adjustment, you need to access variable resistors VR1-VR3 on
the Main Board (see the figure at right). Remove the access plate on top of the
Upper Paper Guide (see Figure 4-13
Mode (see Using the Self-Diagnostic Mode
Menu," and then select "Sensors" (see
instructions below for each sensor that you need to adjust.
When making this adjustments, avoid strong light
(such as sunlight) near the printer. These sensors are
photo-sensitive and do not function properly under
strong lighting.

Paper Edge Sensor
1. Move the carriage left and right manually and make sure that the signal
level indicated on the LCD is smaller than 18H (hexadecimal value).
2. Place a sheet of coated ink jet paper in the paper path, and lower the
Paper Release Lever to lock the paper in position.
3. Move the carriage over the paper so that the Paper Edge Sensor is located
in the middle of the paper.
4. Adjust VR1 on the Main Board so that the signal level indicated on the LCD
is 80H ±8H (between 78 and 88, hex).

Front Paper Sensor
1. As above, make sure that the signal level indicated on the LCD is smaller
than 18H.
2. Place a sheet of coated ink jet paper in front of the Front Paper Sensor
located on the Lower Paper Guide; lower the Paper Release Lever to lock
the paper in position.
Adjustments
on page 64). Enter the Self-Diagnostic
on page 108), select "Test
Sensors on page 112). Then follow the
3. Adjust VR2 on the Main Board so that the signal level indicated on the LCD
is 87H ±8H (between 7F and 8F, hex).

Rear Paper Sensor
1. As above, make sure that the signal level indicated on the LCD is smaller
than 18H.
2. Place a sheet of coated ink jet paper over the Rear Paper Sensor located
in the Upper Paper Guide, and hold it in place or secure it with tape.
3. Adjust VR3 on the Main Board so that the signal level indicated on the LCD
is 8AH ±8H (between 82 and 92, hex).
Table 5-14. Sensor Adjustment Values
Sensor
Paper Edge Sensor
Front Paper Sensor
Rear Paper Sensor
Without Paper With Paper
18H or less 80H ±8H
18H or less 87H ±8H
18H or less 8AH ±8H
136