Epson LQ-1050X User Manual page 201

3. Reattach the power cable, making sure that the small fins on the
white plastic clip are toward the inside of the printer. Take extra
care to see that the holes of the clip are aligned with the pins of
the connector.
4. Holding the interface board level, rotate it clockwise into
position and attach it to the main board. Make sure the connector
pins are properly inserted into the mating connector.
Using the Printer Options
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