Lexmark C750 Service Manual - Page 142

5060-00x 500-Sheet drawer option service check If the paper does not feed from the 500-sheet option, see "Autocompensator service check" on page 2-114. Whenever the 500-Sheet Tray is removed, use care as the autocompensator may be in its down position which could result in damage to the autocompensator assembly. The tray empty sensor, paper low sensor, and pass thru sensor for any installed tray x (x=2 through 4) can be checked using the Input Tray "Sensor Test" on page 3-24. The base printer does not recognize that tray x is installed. Step 1 2 Action and questions Is tray x the only paper input option that is not recognized? Make sure the printer and any option above tray x is installed correctly. Is the printer and any options installed correctly? 3 Verify correct installation of the lower options autoconnect cable to engine board connector J5. Is the cable to J5 installed correctly? 4 Autoconnect cables-check the autoconnect from the printer or option above tray x. Check for cuts, pinched wiring, or damage to the contacts in the connector. Are there any problems with the autoconnect cables? 5 Tray x autoconnect cable-check the tray x autoconnect cable(s) for correct installation at the tray x system board. Are the tray x autoconnect cable(s) connected correctly? 6 Tray x autoconnect cable continuity-check the continuity of the tray x autoconnect cable(s). Is there continuity? 7 Disconnect J5 from the engine board and check the voltages on connector J5 on the engine board. The voltages should measure: Note: All voltages are approximate values. Connector pins J5-1 J5-3 J5-5 J5-6 J5-8 Voltage +24 V dc +5 V dc +5 V dc +5 V dc +5 V dc Yes Go to step 5 Go to step 3 No Go to step 2 Install the option correctly and recheck Install the cable correctly and recheck Go to step 5 Go to step 4 Repair or replace as necessary Go to step 6 Install the cables correctly and recheck Go to step 7 Replace electronic size sensing assembly (includes the system board) Replace the engine board Replace electronic size sensing assembly (includes the system board) Are the voltages correct? 2-108 Service Manual