• Code: 900
• Description: RIP Software
• Remedy: Contact your customer service center, or the Lexmark Customer Support Center.

• Code: 910
• Description: DC Motor (1) Locking error - the motor did not stabilize.
• Remedy: A The print cartridge fails to increment the OPC in the cartridge. 1 Print Cartridge(s) Check the print cartridge for correct installation and signs of wear or damage to the cartridge coupling/drive gear. If no problems are found, try a new print cartridge. 2 Coupling Shaft Coupling Coupling Shaft Coupling Spring OPC/Coupling Drive Block Check the operation of the coupling system. If correct, verify the coupling shaft coupling spring is not broken and the coupling is operating properly. If problems are found, repair or replace the OPC/coupling block assembly, or parts. If the coupling system is not operating properly, go to the “Coupling Unit Service Check”.
  B Error Code 910 displays 1 OPC Drive Motor (M 1) Engine Board MK1 Cable Check the OPC drive motor for proper operation. If incorrect replace the following FRUs in the order shown. 1. OPC drive motor assembly 2. Engine board 3. Cable MK 1

• Code: 911, 912
• Description: 911 DC Motor (2) Locking error - the motor did not stabilize. 912 DC Motor The motor stabilized then locking was released.
• Remedy: 1 Fuser Block Assembly Check the paper feed parts in the fuser drive assembly for excessive noise or vibration. Look for loose or worn paper feed parts. • If problems exist, repair or replace the fuser block assembly. • If excessive noise or vibrations exis2 Developer/Paper Feed Motor Assembly (M2) Developer/Paper Feed Motor Cable Engine Board Check the voltages on connector CON 1 on the developer/paper feed motor board. All voltages are approximate values: Pin # Voltage Motor Running Motor Static 1 CS 0 V dc +5 V dc 2 ROIR 0 V dc 0 V dc 3 GND 0 V dc 0 V dc 4 +5 V dc +5 V dc +5 V dc 5 Lo 0 V dc +5 V dc 6 P/S 0 V dc +5 V dc 7 PGND 0 V dc 0 V dc 8 PGND 0 V dc 0 V dc 9 +24 V dc +24 V dc +24 V dc 10 +24 V dc +24 V dc +24 V dc If the voltage on pin 4, 9 or 10 are incorrect, check continuity of the cable. • If correct, disconnect CON 1 from the board assembly and check the voltages on the cable connector. • If incorrect, check continuity of the cable. • If incorrect, replace the cable. • If correct, replace the engine board. • If the voltages on the cable connector are correct, replace the developer/ paper feed motor assembly. If the voltages on pins 1, 5 and 6 always measure approximately +5 V dc, replace the developer/paper feed motor assembly. If the voltages always measure approximately 0 V dc, check the continuity of the cable. • If incorrect, replace the cable. • If correct, replace the engine board assembly.t in the motor assembly, replace the developer/ paper feed motor assembly. • If no problem is located for paper feed parts, the problem may be the engine board assembly.

• Code: 917
• Description: Transfer Belt
• Remedy: A 84 Transfer Belt Exhausted message displays and the OPC/ITM drive gear is not turning.
  1 Gear A10 Transfer Belt Connecting Shaft Dowel Pin Gears A6, A71 OPC Motor (M x) Check gear A10 for proper operation and signs of wear or breakage. Be sure the transfer belt connecting shaft dowel pin is correctly located in the back of gear A10. If a problem is found, repair as necessary. Check gears A6 (2 each) and gear A71 for signs of wear or breakage. Be sure the OPC drive motor gear is properly contacting gears A6 in the motor mounting stay A assembly. Be sure the motor is operating correctly. Repair or replace as necessary.
  B 84 Transfer Belt Exhausted or 917 Error Code displays, the OPC/ ITM drive gear is turning and a new ITM does not fix the problem.1 Transfer Belt Position Sensor (PS200) Engine Board MSN Cable The transfer belt sensor is a LED Optotransistor pair that detects the belt by sensor (PS200) reflecting light from the LED to the belt in the ITM and back to the phototransistor. The sensor checks when the transfer belt has reached home position. Check the transfer belt sensor for correct operation. If the sensor is not operating properly, replace the FRU's in the following order. 1. Belt position sensor 2. Engine board 3. MSN cable
  C The waste toner bottle is not detected, and a new ITM does not fix the problem. 1 Waste Toner Sensor Board (PQ350) Engine Board MSN Cable Check the waste toner sensor board cable and MSN cable connections. • If correct, check the waste toner sensor for proper operation. • If the sensor is not operating correctly, replace the following FRU's, in the order shown: 1. Waste toner sensor board 2. Engine board 3. MSN cable

• Code: 918
• Description: Fan Stalled The main fan has stalled, or locked up.
• Remedy: 1 Main Fan Cable Be sure the fan cable in-line connector is connected properly to the CRF cable from the engine board. 2 Main Fan Engine Board Cable (CRF) Engine Board Manually spin the fan and verify it rotates freely. • If incorrect, replace the engine board (CRF) to fan cable. • If the fan turns freely, turn the printer off and check the voltages below from the fan connector to the printer board cable (CRF), as you turn the printer on. Fan cable connector: • Pin 1 (Green) 0 V dc (running and not running) • Pin 2 (Yellow) 0 V dc (fan not running) +5 V dc (fan running) • Pin 3 (Red) 0 V dc (fan not running) +24 V dc (fan running) If any of the voltages are incorrect, disconnect the fan cable from the engine board cable and check the voltages on the engine board cable connector. • If correct, replace the main fan. • If incorrect, check the engine board cable (CRF). • If incorrect, replace the cable. • If correct, replace the engine board.

• Code: 920, 921
• Description: 920 Fuser Error Indicates that the fuser is below temperature when printing. 921 Fuser Error Indicates that the fuser is below temperature and the system is detecting a thermistor short
• Remedy: 1 Thermistor Be sure the thermistor is clean and positioned properly. Check the following resistances of the thermistor: • Hot: (CN18-1 and CN18-2) (engine board) should be approximately 2.0 - 2.5 k ohms. • Cold: Should be approximately 150k to 250k ohms. If incorrect, replace the thermistor. 2 Engine Board HCU Cable Check the HCU cable and fuser to engine board cable, to be sure the contacts in the HCU cable (the autoconnect) are not bent or damaged. • If damaged, replace the HCU cable. • If the no damage is detected, be sure the cable is installed correctly at CN18 on the engine board. If the cable is good, replace the engine board. Error codes 923 and 924 may display for a hot fuser failure.

• Code: 922
• Description: 922 Fuser Error Indicates that the fuser temperature failed to increase.
• Remedy: 1 Fuser Assembly Fuser Lamp Circuit Be sure the fuser assembly is correctly installed and locked down. Disconnect the AC power cord from the printer. Disconnect CN406 from the LVPS board and check for continuity between pins 1 and 2 on the CN406 cable connector. • If incorrect, go to step 2. • If correct, check the voltage between CN406 Pin 1 and 2. The voltage should read the same as the AC line voltage. • If incorrect replace the LVPS. 2 Fuser Lamp Thermostat Fuser Lamp Contacts Remove the fuser assembly from the printer. Note: Take care not to damage any pins when checking continuity. Check continuity between the two outer fuser lamp contacts of the autoconnector (HCU cable) located on the bottom of the fuser assembly. • If correct, go to step 3. • If incorrect, check the fuser lamp, thermostat, fuser lamp contacts and HCU cable, replacing any defective parts. 3 Interlock Switches Go to the “Cover Interlock Service Check”.

• Code: 923, 924
• Description: 923 Fuser Error Fuser is too hot during printing or when printer is idle. 924 Fuser Error Indicates that the system has detected that the thermistor is open.
• Remedy: 1 Fuser: • Assembly • Hot Roll • Backup Roll Bearings Check the fuser assembly for signs of overheating or damage, especially the hot roll and backup roll. Also check for contaminants such as label glue or excessive toner buildup. • If contaminants are found, repair as necessary or replace the fuser assembly. • If damage from overheating is found, replace the fuser. 2 Thermistor Assembly Engine Board Check for a shorted thermistor by measuring across the connector located in the cable guide. • If the thermistor is shorted, replace the thermistor. • If replacing the failing thermistor does not fix the problem, replace the engine board. Check for signs of damage or contamination to the thermistor assembly. If no problem is found, check the resistance of the thermistor. Hot: CN18-1 to CN18-2: Approximately 2.0k - 2.5k ohms Cold: Approximately 150k to 250k ohms If incorrect, replace the thermistor. Check for an open in the thermistor circuit in the fuser assembly. Be sure the thermistor is properly connected to the thermistor cable in the bottom of the cable guide.