Lower Pinch Roller Removal; Main Logic Board Removal - Lexmark 4227 - Forms Printer B/W Dot-matrix Service Manual

4227-300

Lower pinch roller removal

1. Remove the ribbon cover and the ribbon.
2. Remove the U-shaped ground spring (1).
3. Release the left and right pinch roller springs (2).
4. Move the carrier to the right as far as it will go.
5. Lift the left end of the lower pinch roller and move it to the left
until the right end clears the carrier. Be sure not to lose the right
bearing.
6. Remove the shaft to the right.

Main logic board removal

1. Remove the top cover. See
2. Disconnect all cables connected to the main logic board.
3. Remove the three screws at the rear edge of the board, and
then remove the board.
4. Remove the EPROM from the old board and install it on the
new one.
To reinstall:
After replacing the main logic board, recheck the
adjustment" on page 4-3
adjustment" on page
"Top cover removal" on page
and the "Printhead-to-platen gap
4-2.
"Bidirectional print
Repair information
4-5.
4-21