Lexmark T642 Service Manual - Page 142

4061-xx0 271.xx Paper Jam - Check Bin x, POST incomplete FRU 1 Upper pass thru sensor flag assembly Upper control board Action Check the flag for correct operation, binding, broken parts, or interference from the sensor cable. If incorrect, repair as necessary. If correct, make sure the lower pass thru sensor is correctly connected to J3 on the lower control board. Disconnect the pass thru sensor cable and check the voltage at J3-3. The voltage measures approximately +5 V dc. If incorrect, check the voltage at J3-2. The voltage measures approximately 0 V dc. If incorrect, replace the sensor assembly. If this does not fix the problem, replace the highcapacity output stacker option. Input sensor service check Service tip: Run the Base Sensor Test. Check the input sensor for proper operation. The display changes from open to closed as the sensor flag is manually moved in and out of the sensor. FRU 1 Input sensor flag 2 System board 3 Input sensor cable Action Check the input sensor flag for damage and proper operation. If a problem is found, repair as necessary. Check for approximately +5 V dc at J15-10 on the system board. If incorrect, replace the system board. Check the continuity of the input sensor cable section of the front wiring harness. If incorrect, replace the harness. If correct, replace the input sensor assembly. Input tray(s) service check Optional 250-sheet and 500-sheet trays Service tip: Try all the other input paper sources to make sure they are properly feeding paper. For 990 Error Code- Service Tray x, x= displays the number of the tray that has a problem or needs service. FRU 1 Tray x Option system board or compensator assembly or autoconnect cable Action Check the autoconnect cables and connectors for damage. If the cables, connectors, and connections are good, replace the FRUs in the following order: • Autocompensator assembly option • Replace the option. 2-102 Service Manual