Xerox Phaser 5500

• Code: U3-5
• Description: Laser Motor Failure - U3-5 Polygon Motor Rotation The Scanner Motor, located in the Laser Assembly, failed.
• Causes: • Drum Cartridge • Laser Assembly • Engine Control Board
• Remedy: 1 Check the Drum Cartridge installation. Is the Drum Cartridge installed properly? Go to Step 2. Correct the installation. 2 Test the Scanner Motor. Run the Service Diagnostics Laser Scan Motor test. Does the motor run? Replace Laser Assembly or Engine Control Board. Go to Step 4. 3 Check the Laser connection. Are P/J140 and P/J406 connected? Go to Step 4. Connect the Laser Assembly. 4 Check the Laser connections. Are P/J130, P/J620 and P/J406 connected? Go to Step 5. Connect P/J130, P/J620 and P/ J406. 5 Check continuity between the Laser and the Engine Control Board. Is there continuity on each wire between P/ J140 <=> P/J406? Go to Step 6. Repair the wiring. 6 Check continuity between the Laser and the Engine Control Board. Is there continuity on each wire between P/ J130 <=> P/J406? Go to Step 7. Repair the wiring. 7 Check for +5 V to the Laser. Is there +5 V across P/J140-8 (+) <=> ground? Go to Step 8. Replace the Engine Control Board. 8 Check for +24 V to the Laser. Is there +24 V across P/J130-5 (+) <=> ground? Replace the Laser Assembly. Replace the Engine Control Board.

• Code: U4-1
• Description: Fuser Failure - U4-1 On Time NOTE: Following display of this error, leave power applied for 7 minutes, then cycle printer power. If the error reoccurs, proceed with troubleshooting procedure. The Fuser failed to reach temperature within the warm-up period. Possible faults are: • During the Warm-Up period, the Control Thermistor does not detect the Ready temperature even when the specified time has passed. • During the Standby period, the Control Thermistor does not detect the required temperature even when the specified time has passed. • During idling after power-on, the Control Thermistor does not detect the idling stop temperature even after the specified time has passed. • During print, the Control Thermistor does not detect the required temperature even when the specified time has passed.
• Causes: • Fuser • LVPS
• Remedy: 1 Check the Fuser for a paper jam. Open Door A. Is there a paper jam in the Fuser? Remove the paper. Go to Step 2. 2 Check the Fuser installation. Is the Fuser installed properly? Go to Step 3. Correct the installation. If the error persists, replace the Fuser and go to Step 10. 3 Check continuity on the junction connector. WARNING Allow the Fuser to cool. Remove the Fuser. Is there continuity on the pins? Go to Step 4. Replace the Fuser. 4 Check Fuser resistance. Is the resistance across P/J600-1 and P/ J600-11 less than or equal to 100 ohms? Go to Step 5. Replace the Fuser. 5 Check Fuser resistance. Is the resistance across P/J600-4 and P/ J600-11 less than or equal to 100 ohm? Go to Step 6. Replace the Fuser. 6 Check Fuser resistance. Is the resistance across P/J600-7 and P/ J600-11 less than or equal to 100 ohm? Go to Step 7. Replace the Fuser. 7 Check Fuser resistance. Is the resistance across P/J131-1 and P/ J131-2 more than or equal to 3 k-ohm? Go to Step 8. Replace the Fuser. 8 Check Fuser resistance. Is the resistance between P/J132-1 and P/ J132-2 greater than or equal to 3 k-ohm? Go to Step 9. Replace the Fuser. 9 Check Fuser resistance. Is the resistance across P/J133-1 and P/ J133-2 greater than or equal to 3 k-ohm? Go to Step 10. Replace the Fuser. 10 Check Fuser connection. Is P/J6 connected? Go to Step 11. Connect P/J6. 11 Check continuity between the Fuser and LVPS. Is there continuity on each wire between P/ J600 <=> P/J6? Go to Step 12. Repair the wiring. 12 Check for +5 V to the Fuser. Is there +5 V between these pins? • P/J6-1 <=> P6-2 • P/J6-1 <=> P6-3 • P/J6-1 <=> P6-4 Replace the Fuser. Replace the LVPS. 13 Check the LVPS and the Engine Control Board connection. Are P/J401 and P/J525 connected? Replace the Engine Control Board. Connect P/J401 and P/J525.

• Code: U4-2 ... U4-5
• Description: Fuser Failure - U4-n Over Heat / Thermistor. • Fuser Failure - U4-2 Over Heat Temp • Fuser Failure - U4-3 FS1 Thermistor • Fuser Failure - U4-4 FS2 Thermistor • Fuser Failure - U4-5 Pressure Roller Thermistor
• Causes: • Fuser • LVPS
• Remedy: 1 Check the Fuser installation. Is the Fuser installed properly? Go to Step 2. Correct the installation. 2 For FS1 Thermistor Only. Is the resistance across P/J131-1 and P/ J131-2 more than or equal to 3 k-ohm? Go to Step 3. Replace the Fuser. 3 For FS2 Thermistor Only. Is the resistance between P/J132-1 and P/ J132-2 greater than or equal to 3 k-ohm? Go to Step 4. Replace the Fuser. 4 For Pressure Roller Thermistor Only. Is the resistance across P/J133-1 and P/ J133-2 greater than or equal to 3 k-ohm? Go to Step 5. Replace the Fuser. 5 Check the Fuser connection. Is P/J6 connected? Go to Step 6. Connect P/J6. 6 Check continuity between the Fuser and LVPS. Is there continuity on each wire between P/ J600 <=> P/J6? Go to Step 7. Repair the wiring. 7 Check power to the Fuser. Is there +XX V across P/JXXX (+) <=> ground? Replace the Fuser. Replace the LVPS.

• Code: U4-7
• Description: Fuser Failure - U4-7 Cold Sagging The Fuser temperature regulation failed. NOTE: Following display of this error, leave power applied for 7 minutes, then cycle printer power. If the error reoccurs, proceed with troubleshooting procedure.
• Causes: • Fuser • LVPS • Engine Control Board
• Remedy: 1 Check the Fuser for a paper jam. Open Door A. Is there a paper jam in the Fuser? Go to Step 2. Remove the paper. 2 Check the Fuser installation. Open Door A. Is the Fuser installed correctly? Go to Step 3. Install the Fuser correctly. 3 Test the Fuser Exit Sensor operation. 1. Open Door A. 2. Run the Service Diagnostics Fuser Exit Sensor test. Does sensor state change each time the Fuser is installed or removed? Go to Step 5. Go to Step 4. 4 Check the resistance of the Fuser. Is there an open circuit in the Center Thermistor between J131-1 and J131-2? Is the resistance of the Rear STS across J131-1 and J131-2 equal or greater than 3 kohm? Go to Step 7. Replace the Fuser. 5 Check the Pressure Roller Thermistor resistance. Is there an open circuit in the Pressure Roller Thermistor between J133-1 and J133- 2? Is the resistance of the Pressure Roller Thermistor across J133-1 and J133-2 more than or equal to 3 k-ohm? Go to Step 6. Replace the Fuser. 6 Check the Fuser for connection. Is LVPS P/J6 connected? Go to Step 7. Connect P/J6. 7 Check the Fuser connections. Are P/J410, P/J607, P/J600, P131 and P133 connected? Replace Engine Control Board. Connect P/J410, P/J607, P/J600, P131 and P133.

• Code: U4-9
• Description: Fan Failure - U4-9 Fan Defect The Fuser Fan failed.
• Causes: • Fuser Fan • Motor Assembly • Engine Control Board
• Remedy: 1 Check the Fuser Fan installation. 1. Remove the I/P Board Cover. 2. Remove the Upper Rear Cover. Go to Step 2. Correct the installation. 2 Check if the Fuser Fan rotates. Does the Fan rotate? Go to step 6. Go to step 3. 3 Test the Fuser Fan. Run the Service Diagnostic Fuser Fan test. Does the Fuser Fan operate properly? Go to step 6. Go to step 4. 4 Check the Fuser Fan connection (CN102). Is the Fan connected? Go to Step 5. Connect the Fan. 5 Check continuity between the Fan and Motor Assembly (CN102). Is there continuity on each wire? Go to Step 6. Replace the Fan. 6 Check for +24 V to the Fuser Fan. Is there +24 V across CN102-3(+) <=> ground? Replace the Fan. Replace the Fan. If the error persists, replace the Engine Control Board, then replace the Motor Assembly.

• Code: U5-1
• Description: Toner Motor Failure - U5-1 Motor Rotation The Toner Dispense Motor failed to rotate.
• Causes: • Toner Cartridge • Toner Dispense Assembly • Toner Dispense Motor • Engine Control Board
• Remedy: 1 Check the Toner Cartridge installation. Reinstall the Toner Cartridge. Does it operate properly? Problem solved. Go to Step 2. 2 Check Toner Dispense Assembly rotation. Does the gear located at the lower part of the Toner Dispense Assembly rotate? Go to Step 3. Restore proper operation. 3 Check Toner Dispense Assembly clogging. Is the pipe located at the lower part of the Toner Dispense Assembly clogged? Go to Step 4. Clean the pipe. 4 Test Dispense Motor operation. Run the Service Diagnostics Dispense Motor test. Does the motor operate? Replace the Engine Control Board (page 8-89). Go to Step 5. 5 Check the Dispense Motor for connection. Are P/J216 and P/J420 connected? Go to Step 6. Connect P/J216 and P/J420. 6 Check continuity between the Dispense Motor and Engine Control Board. Is there continuity on each wire between P/ J216 <=> P/J420? Go to Step 7. Repair the wiring. 7 Check for +24 V at the Dispense Motor. Is there +24 V across P/J216-1 (+) <=> ground? Replace the Dispense Motor. Replace the Engine Control Board.