Lexmark T522 Service Manual - Page 73

4520-xxx Duplex Unit Service Check The printer does not recognize the Duplex Unit is attached. The printer does not recognize tray options below the duplex unit are installed. FRU 1 Fuse F1 on Duplex Unit System Board 2 Autoconnect Cables/ Connectors Action If fuse F1 is blown, replace the fuse. If fuse F1 continues to blow, check the stepper motor for a short between the motor case and pins J3-1 through J3-4. If no problem is found, check the D.C. servo motor pins J1-1 and J1-2 to the motor housing for a short. If a short is found, replace the motor assembly. If no short is found, replace the system board. Check the autoconnect cables for damage to the cables or the pins in the connectors. If damaged, replace the cable(s). If no damage is found, check to make sure the cables are connected to J9, J10, J11 and J12 on the duplex system board. If no problem is found, replace the duplex system board. Diagnostic Information 2-45