• Code: 111.69
• Description: Too many fake HSYNCs while aligning printhead.
• Remedy: Step 1: Check the printhead unit cables JLSU1 and J6 for proper connection. Are they properly connected? Yes: Go to step 2. No: Reseat the cables.
  Step 2: Inspect the printhead cables and connectors. Are they free of damage? Yes: Replace the controller board. No: Replace the printhead.

• Code: 121.07
• Description: Fuser has been on for more than allowed after a gap blowout, and the temperature is still too cold.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.08
• Description: Fuser was under temp when page was in fuser.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.20
• Description: Fuser undertemp during steady state control. Can ocurr in printing or standby modes.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.22
• Description: Fuser did not warm enough to start line voltage detection.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.23
• Description: Fuser took too long to heat to line detection temp.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.24
• Description: Fuser never reached detection temperature.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.

• Code: 121.25
• Description: After line voltage detection, control did not roll over to steady state control in time.
• Remedy: Step 1: 1. Restore the engine settings to their defaults: Diagnostics Menu >Printer Setup >Defaults 2. Restore the EP setup settings to their defaults: Diagnostics Menu >EP Setup >Defaults Does the problem remain? Yes: Go to step 2. No: The problem is solved.
  Step 2: • Check the fuser cables JTHERM1 and JEXIT for proper connection to the controller board. • Check the cable PCN5 for proper connection to the power supply. Are they properly connected? Yes: Go to step 3. No: Reseat the cables.
  Step 4: 1. Turn off the printer. 2. Remove the rear door and cover. 3. Disconnect the fuser cable connected to PCN5 of the power supply. 4. Check for approximate correct resistance on the fuser cable: - 220V fuser - 43 ohms - 110V fuser - 10 ohms - 100V fuser - 8 ohms Is the resistance equal to any of the above values? Yes: Perform an LVPS service check. No: Replace the fuser.
  Step 5: Check the fuser rollers, belts and gears for damage and debris. Are they free of damage and debris? Yes: Perform a cooling fan service check and LVPS service check. No: Replace the fuser.