• Code: 4501-111.31
• Description: Laser malfunction
  Printhead never delivered HSYNCs.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.32
• Description: Laser malfunction
  Printhead lost HSYNCs.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.40
• Description: Laser malfunction
  Wrong printhead installed.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.50
• Description: Laser malfunction
  Open-loop printhead error, open-loop sweep state.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.51
• Description: Laser malfunction
  Open-loop printhead error, open-loop sweep state.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.52
• Description: Laser malfunction
  Open-loop printhead error, check prelim amp state.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.53
• Description: Laser malfunction
  Open-loop printhead error, enable amp Kp state.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.

• Code: 4501-111.54
• Description: Laser malfunction
  Closed-loop printhead error, amp Kp failed to converge.
• Causes: • Printhead (PH) • Controller board (CTLB)
• Remedy: 1 Check PH cables JLSU1 and J6 for proper connection. Reseat the cables if any abnormality is found. 2 Inspect PH cables and connectors. 3 Replace CTLB. 4 Replace PH.