Lexmark C720 Service Manual - Page 125

5024-001 910-Developer Motor (DM) Drive Service Check FRU 1 • Toner Cartridge • Developer Gear Unit • Developer Motor 2 Cable and Connectors 3 Developer Motor (DM) Action If any unusual rotation noise is heard while printing, check the toner cartridge and replace, if necessary. If the noise continues after the toner cartridge is replaced, check the developer gear unit by manually turning the motor. • If any damage to the gears is found, replace the developer gear drive unit. • If the noise continues, replace the developer drive motor (DM). If the developer motor does not turn On: • Ensure the connector DCN9 on the IOD1 P.W.B. board and the connector for the developer motor are completely connected. • Ensure connectors DCN1 on the IOD1 and 11CN on the main engine (MCTL P.W.B.) board are completely connected. • Replace any damaged parts. Check for +24V between DM1-4 and DM1-6 • DCN9-4 and DCN9-6 • DCN10-3 and DCN10-4 Check for +5V between DM1-5 and DM1-9 • DCN9-5 and DCN9-9 • DCN10-7 and DCN-9 If either +24V or +5V is found while checking these connectors, replace the developer motor (DM). Diagnostic Information 2-45