Lexmark T620 Service Manual - Page 111

4069-5XX/7XX Tray X Empty message displays. Tray does not respond to loading paper. No response from the front door switch. FRU 1 High Capacity Feeder Option Control Board 2 Elevator Top Optical Sensor Cable Elevator Top Optical Sensor Action Check the voltage on the board at J4-2 (green). The voltage measures approximately +5 V dc. If incorrect, disconnect the cable at J4 and check the voltage again. If incorrect, replace the high capacity feeder option control board. Check the continuity of the sensor cable. If incorrect, replace the cable. If correct, replace the top optical sensor assembly. Tray X Paper Low Message displays when the high capacity feeder input tray is full or has adequate paper in the tray. FRU 1 Paper Low Switch Paper Low Switch Cable High Capacity Feeder Option Control Board Action Run the sensor diagnostics for tray X (X=the number that represents the high capacity input tray). If the test fails, check the voltage at J3-1 (gray). The voltage measures approximately +24 V dc. If incorrect, disconnect the paper low switch cable from J3 and measure the voltage again on J3-1. If incorrect, replace the high capacity feeder option control board. If correct, check the cable for a short between pins 1 and 2 on the cable. If incorrect, replace the cable. If correct, check the switch for a bent or deformed actuator lever or defective switch. If incorrect, replace the switch. Diagnostic Information 2-83