How to repair the print head on HP Designjet T120 T520

Introduction

This tutorial will guide you through the process of repairing the print head on HP Designjet T120 and T520 printers. If you're experiencing issues with print quality or communication errors, this step-by-step guide will help you troubleshoot and fix the problem, ensuring your printer runs smoothly again.

Step 1: Gather Necessary Tools and Materials

Before starting the repair, make sure you have the following items on hand:

• New chip board for HP print heads (compatible with 711 cartridges)
• Screwdrivers (Phillips and flat-head)
• Tweezers
• Clean, lint-free cloth
• Isopropyl alcohol for cleaning

Step 2: Remove the Print Head

Follow these steps to safely remove the print head from your printer:

1. Turn off the printer and unplug it from the power source.
2. Open the printer cover to access the print head assembly.
3. Carefully detach the print head by:
   • Lifting the locking lever.
   • Gently pulling the print head out of the carriage.

Step 3: Inspect the Print Head

Once the print head is removed, inspect it for any visible damage:

• Check for broken or bent contact springs.
• Look for clogged nozzles or any residue on the print head.

Step 4: Clean the Print Head

Cleaning the print head can resolve many issues related to print quality:

1. Dampen a lint-free cloth with isopropyl alcohol.
2. Gently wipe the print head contacts to remove any dirt or ink buildup.
3. For clogged nozzles, you may need to soak the print head in warm water for a few minutes.

Step 5: Replace the Chip Board

If the chip board is damaged, follow these steps:

1. Locate the chip board on the print head.
2. Use a flat-head screwdriver to carefully pry off the old chip board.
3. Align the new chip board and press it into place until it clicks securely.

Step 6: Reinstall the Print Head

Once the repairs and cleaning are done, reinstall the print head:

1. Insert the print head back into the carriage.
2. Lower the locking lever to secure it in place.
3. Close the printer cover.

Step 7: Test the Printer

After reassembling the printer, perform a test print:

1. Plug the printer back into the power source and turn it on.
2. Run a test print from the printer's control panel or your computer.
3. Check for any errors or print quality issues.

Conclusion

You've successfully repaired the print head on your HP Designjet T120 or T520 printer. Regular maintenance, including cleaning and inspecting the print head, can prolong its lifespan and improve print quality. If issues persist, consider consulting a professional technician or replacing the print head altogether.