Lexmark C920 Service Manual - Page 93

5056-XXX Paper feed unit service check Note: These tests can also be performed on the expansion paper-feed units. FRU 1 Turn guide door sensor Paper tray level motor Printer controller board 2 Paper out sensor Paper feed unit Paper level sensor Action • Turn the printer on. • Open the door. • Check the operator panel for "Close Door" message. • Bypass the turn guide door open sensor*. • Pull out and replace the cassette. Listen for the paper tray level motor to activate. (The tray may or may not rise. The motor makes a low pitched vibrating sound.) - If the paper tray level motor operates and the "Close Door" message fails to appear, replace the turn guide door sensor. - If the "Close door" message appears and the paper tray level motor fails to operate, replace the paper tray level motor. - If the paper tray level motor fails to operate, and the "close Door" message fails to appear, check CN3, CN4, and CN5 on the printer controller board. If they are properly connected, replace the printer controller board. • Turn the printer on, and open the turn guide door. Bypass the turn guide door open sensor*. • With the paper tray empty and the paper out sensor blocked, pull out and replace the cassette. - If the tray rises and stays in place, check for a dirty paper out sensor, and inspect the ball actuator on the paper feed unit. - If the ball actuator is stuck or broken, replace the paper feed unit. - If the ball actuator is good, replace the paper out sensor. - If the tray (x) empty message is displayed, check the paper out sensor to ensure it is in place. • Turn the printer on, and open the turn guide door. Bypass the turn guide door open sensor*. • Block the paper out sensor. • With the tray empty, pull out and insert the cassette. - If the tray fails to rise, check for a dirty paper level sensor or broken casette present actuator. With the turn guide door open, remove and reinsert the paper tray. - If the paper feed roll fails to go up when the paper tray is reinserted, replace the paper feed unit. - If the actuator is broken, replace the paper feed unit. - If the actuator is good and the sensor was clean, replace the paper level sensor. - If the tray too full message is displayed, clean or replace the sensor. Diagnostic information 2-51