Lexmark C750 Service Manual - Page 154

5060-00x Duplex option service check Before proceeding with this service check: 1. Check for any pieces of media or obstructions in the duplex paper path that might cause a paper jam. 2. Check for correct installation of the front duplex jam tray and right side clearance tray. 3. Check the duplex option for any signs of loose, damaged, contaminated, or warped parts that might cause a jam. Duplex not recognized as being installed Step 1 2 Action and questions Is Duplex option the only option installed beneath the base printer? Except for the duplex option, remove any other paper options installed beneath the base printer. Does the printer recognize the duplex option as being installed? Yes Go to step 3 The problem is in one of the option(s) that is installed beneath the printer. Try to isolate which of the options is causing the problem. Go to step 4 No Go to step 2 Go to step 3 3 Make sure the duplex option is correctly installed. Is the duplex option installed correctly? Install the duplex option correctly Install the cable correctly 4 Make sure the bottom options cable connector is snapped firmly into the bottom of the base machine. Is the cable connector mounted correctly? Go to step 5 5 Make sure the options cable is installed correctly to engine board connector J5. Is the cable installed correctly? Go to step 6 Install the cable correctly 6 Check the voltages on connector J5 on the engine board. The voltages are measured with the printer in standby mode: Note: All voltages are approximate values. Connector pin Voltage J5-1 J5-3 J5-5 J5-6 J5-8 +24 V dc +5 V dc +5 V dc +5 V dc +5 V dc Go to step 7 Replace the engine board. See "Engine board removal" on page 4-29. Are the voltages correct? 2-120 Service Manual