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Phone · Samsung · Galaxy S21 Ultra

Samsung Galaxy S21 Ultra Screen Replacement

Screen Replacement guide for the Samsung Galaxy S21 Ultra

Moderate
~49 min
23 steps

Before you begin

Tools

  • Heat gun or hairdryer
  • Suction cup
  • Plastic opening picks
  • Phillips #00 screwdriver
  • Tweezers
  • SIM eject tool
  • Plastic spudger

Parts / materials

  • Replacement Galaxy S21 Ultra screen assembly
  • Pre-cut screen adhesive strips
  • Rear cover adhesive strips
  • Isopropyl alcohol (99%)

Safety

  • Wear safety glasses to protect your eyes from loose glass fragments while removing the damaged display.
  • Disconnect the battery press connector before removing or installing internal components to prevent short circuits.
  • Handle lithium-ion batteries with care; do not puncture, bend, or apply excessive heat directly to the battery.

Overview

# Samsung Galaxy S21 Ultra Screen Replacement Repair Guide Action-specific screen replacement walkthrough for the Samsung Galaxy S21 Ultra. About 49 minutes across 23 steps. This DIY guide walks through screen replacement on the Samsung Galaxy S21 Ultra (Galaxy S series phone). Before you open the device, confirm the exact model number on the Samsung settings screen or rear housing so your replacement part matches the Galaxy S21 Ultra specifically—not a similar Galaxy S sibling. Most DIY techs finish this Samsung Galaxy S21 Ultra screen replacement in about 49 minutes when parts and tools are ready. Difficulty is rated intermediate for this model. Recommended tools for this Samsung Galaxy S21 Ultra job: Heat gun or hairdryer, Suction cup, Plastic opening picks, Phillips #00 screwdriver, Tweezers, SIM eject tool, Plastic spudger. Parts and supplies: Replacement Galaxy S21 Ultra screen assembly, Pre-cut screen adhesive strips, Rear cover adhesive strips, Isopropyl alcohol (99%). Power the Galaxy S21 Ultra off completely, remove SIMs/SD cards if present, and work on a clean, well-lit surface with a magnetic mat for screws. If a step feels wrong for your Samsung Galaxy S21 Ultra, stop and compare the connector layout to the photos in this guide. When you prefer a same-day pro repair in Seattle instead, LML Repair can handle screen replacement for this model with tested parts and a workmanship warranty.

Step-by-step

  1. 1

    Power off the device

    1 min

    Press and hold the side button and volume down button, then select Power Off on the screen. Ensure the phone is completely powered down before proceeding.

  2. 2

    Heat the back glass panel

    3 min

    Use a heat gun or hairdryer to apply heat evenly along the outer edges of the rear glass for 2-3 minutes. This softens the internal adhesive holding the glass.

  3. 3

    Attach suction cup to back glass

    1 min

    Place a suction cup onto the lower third of the rear glass cover. Press firmly down to secure a tight vacuum seal.

  4. 4

    Slice through back cover adhesive

    4 min

    Pull up on the suction cup to create a small gap, then insert a plastic opening pick under the edge. Gently slide the pick along the perimeter to slice through the adhesive.

  5. 5

    Remove the rear glass cover

    1 min

    Lift the rear glass cover straight off the frame once all adhesive is cut. Set the back glass aside on a clean surface.

  6. 6

    Unscrew the wireless charging coil

    3 min

    Use a Phillips #00 screwdriver to remove the 6 screws securing the wireless charging coil and NFC pad. Keep the screws organized for reassembly.

  7. 7

    Disconnect and remove wireless charging coil

    2 min

    Use a plastic spudger to gently pop the wireless charging coil connector off the motherboard. Peel the coil off the phone frame and remove it.

  8. 8

    Unscrew the upper motherboard bracket

    2 min

    Remove the remaining Phillips screws securing the plastic motherboard cover bracket. Store these screws separately from the coil screws.

  9. 9

    Remove the upper bracket

    1 min

    Use tweezers to lift the plastic motherboard bracket out of the chassis. Be careful not to snag any surrounding flex cables.

  10. 10

    Disconnect the battery cable

    1 min

    Pry the battery press connector straight up from its socket on the motherboard using a plastic spudger. This cuts power to the board to prevent short circuits.

  11. 11

    Unscrew the lower loudspeaker assembly

    2 min

    Use a Phillips #00 screwdriver to remove the screws holding the lower speaker module in place at the bottom of the device.

  12. 12

    Remove the loudspeaker module

    1 min

    Insert a plastic spudger under the loudspeaker assembly and pry up to detach it from the frame chassis.

  13. 13

    Disconnect interconnect cables

    2 min

    Disconnect the main and secondary ribbon interconnect cables from both the motherboard and the bottom sub-board. Remove the loose cables from the phone.

  14. 14

    Disconnect the display cable

    1 min

    Locate the display press connector on the motherboard and use a plastic spudger to pry it straight up.

  15. 15

    Eject the SIM tray

    1 min

    Insert a SIM eject tool into the hole at the bottom of the frame to release the SIM tray. Pull the tray completely out of the device.

  16. 16

    Heat the front display glass

    3 min

    Apply heat around the perimeter of the cracked front display screen for 3 minutes to soften the screen adhesive.

  17. 17

    Attach suction cup to front display

    1 min

    Affix a suction cup to the lower portion of the front screen glass assembly.

  18. 18

    Slice the screen perimeter adhesive

    5 min

    Pull up on the suction cup to create a seam and insert a plastic pick. Carefully slice along all four edges between the screen and frame.

  19. 19

    Remove the old display panel

    2 min

    Lift the damaged display off the frame, threading the attached display cable carefully through the frame slot.

  20. 20

    Clean adhesive from frame

    4 min

    Scrape away remaining adhesive residue on the mid-frame using opening picks and isopropyl alcohol. Ensure the recessed edges are completely clean and dry.

  21. 21

    Apply fresh screen adhesive

    3 min

    Peel the protective backing from the new pre-cut adhesive strip and press it firmly into the internal rim of the mid-frame.

  22. 22

    Install the replacement display

    3 min

    Thread the replacement screen flex cable through the slot in the frame and align the new display panel precisely with the mid-frame.

  23. 23

    Press edges to set adhesive

    2 min

    Gently press along all outer borders of the screen with your fingers for 1-2 minutes to secure a firm adhesive bond.

After your Samsung Galaxy S21 Ultra screen replacement

Power the Galaxy S21 Ultra back on and test the screen replacement function before you put every screw away. Check touch/display response, charging, cameras, buttons, and wireless as relevant to this repair. If something fails after closing the device, reopen carefully and reseat the connectors for this Samsung Galaxy S21 Ultra job before assuming the part is defective. Keep leftover adhesive and screws labeled in case you need a second pass.

Keep learning

Explore more Samsung Galaxy S21 Ultra repair context in the encyclopedia, or open related DIY guides.

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