How to Refurbish Samsung Galaxy Z Flip4: Complete Screen & Mid-Frame Restoration Guide

Foldable smartphones like the Samsung Galaxy Z Flip4 are revolutionary — but also delicate. A cracked back cover, hinge damage, or screen issues like yellow tinting can ruin both functionality and appearance. Fortunately, these issues don’t mean you need a new device.

In this comprehensive refurbishment guide, we’ll walk you through the step-by-step process to restore a damaged Samsung Z Flip4, addressing a yellow-tinted screen, replacing the back cover, and repairing the mid-frame. Whether you’re a repair technician, DIY enthusiast, or running a repair shop, this tutorial will help you transform a broken foldable into a like-new device.

Step-by-Step Samsung Z Flip4 Refurbishment Process

1. Initial Screen Testing

• Turn on the device. Dial *#0*#
• Check touch response and display functionality.
• If both work normally despite screen tint, proceed with refurbishment.

2. Remove the Back Cover

1. Power off the phone.
2. Place the phone on a heating pad set to 90°C (194°F) for 5 minutes.
3. Insert an entry pick along the back cover gap and apply isopropyl alcohol.
4. Slide toward the center hinge area using an opening card.
5. Repeat the process for the upper back cover.

Important: Disconnect the back cover flex cable before fully removing the back.

3. Internal Disassembly

• Apply a camera lens protective sticker.
• Unscrew all metal plates.
• Disconnect:
  • Battery flex cable
  • Hinge flex cable
  • Wireless charging coil
  • Bridge flex cable
• Remove:
  • Front camera
  • SIM card tray
  • Motherboard
  • Charging port
  • Speaker assembly

4. Screen Disassembly

• Reheat the screen area.
• Use IPA and spudger to lift the support frame and remove clips.
• Insert an opening card — avoid cutting the display flex cable at the bottom.
• Peel off adhesive and proceed carefully.

5. Clean Screen Components

• Place the screen on a separator and use electronic glue remover.
• Clean with isopropyl alcohol, sponge, and lint-free cloth.

6. Replace the Damaged Polarizer

1. Insert 0.028mm cutting wire to remove the outer CPI film.
2. Clean again.
3. Use cutting wire to remove the polarizer — keep tension even and parallel.
4. Clean surface with specialty solution and cloth.

7. Apply New Polarizer & Laminate

• Place screen in alignment mold.
• Apply new inner film with polarizer layer.
• Laminate and perform bubble removal.

8. Reassemble the Device

Mid-Frame Restoration

• Pry up both batteries using IPA and blade (carefully).
• Remove power button, speaker, hinge, waterproof strip, and hinge flex cable.
• Clean hinge and install components onto the new mid-frame.
• Test foldability before final connections.

Final Assembly

• Reinstall:
  • Motherboard
  • Front camera
  • Wireless charging coil
  • Charging port module
• Apply screen adhesive, bond screen to mid-frame gently.
• Use frame adhesive for support frame and clips.
• Secure with tape until bonded.
• Apply sealing tape on back cover, remove lens film, and reattach back cover.

9. Final Testing

Power on the phone and verify:

• Screen works correctly
• Touch is responsive
• Folding mechanism functions smoothly

The Samsung Galaxy Z Flip4 has been successfully refurbished!

Tools & Parts List

Tools Used:

• Heating pad (90°C)
• Entry pick & opening card
• Isopropyl alcohol (IPA)
• Spudger, tweezers, screwdrivers
• Lint-free cloth, sponge
• Electronic glue remover
• Separation machine, cutting wire
• Alignment mold, laminator, bubble remover
• Protective stickers, adhesive tapes

Replacement Parts:

• New mid-frame
• Inner film with polarizer
• Back cover
• Hinge flex cable
• Waterproof strip

Glossary of Terms

• Polarizer: Controls light direction in the display. Damaged polarizers cause discoloration like yellow tinting.
• CPI Film: A transparent layer protecting the flexible screen surface.
• Lamination: Bonding display layers using pressure and heat.
• Hinge Flex Cable: Sends signals across the folding hinge. A common failure point in foldable phones.

Repair Key Points:

• When separating the bottom screen, do not slide the opening card all the way down. A display flex cable lies at the bottom. Stop at the position shown on the screen.
• When separating the inner film (polarizer with UTG) from the display layer, it is recommended to use a 0.028mm cutting wire, pulling gently to avoid damaging the display layer.
• The hinge flex cable is fragile; handle it carefully during removal and installation to prevent irreversible damage.

Conclusion

Refurbish Samsung Galaxy Z Flip4 isn’t just possible — it’s practical and rewarding. By carefully replacing the polarizer and back cover, restoring the hinge, and reassembling the phone step-by-step, you can turn a damaged device into a like-new foldable phone.

Whether you’re a repair shop technician or advanced DIYer, this guide will save costs, reduce e-waste, and improve repair confidence. Be sure to test all functions post-assembly for the best result.

Tips & Resources

• 🔗 Check our YouTube channel for the hinge flex cable repair video.
• 📸 Add repair images or video snippets for better clarity.
• 🕒 Estimated repair time: 2–3 hours | Difficulty: 🔧🔧🔧🔧 (Advanced)