Samsung Galaxy S21 Daughterboard Replacement

Avoid inserting tools into non-SIM card tray holes.

• Insert a SIM eject tool, bit, or straightened paper clip into the SIM card tray hole on the bottom edge of the phone.
• Press it in to eject the SIM card tray.
• Remove the SIM card tray.

Inserting into a microphone hole is unlikely to damage it, but be cautious.

Power off your phone completely before starting.

• Apply an iOpener to the bottom edge of the back cover for 2 minutes.
• Alternatively, use a hair dryer, heat gun, or hot plate, but be cautious not to overheat the device, as it may cause damage to the display, internal battery, or plastic back cover.

Apply a suction cup to the phone's back near the center of the bottom edge.

• Pull up on the suction cup with strong, steady force to create a gap between the back cover and frame.
• If you encounter difficulties, consider applying more heat to the edge before retrying.

Once a gap is created, insert an opening pick up to 5 mm into the space.

Slide the pick back and forth along the bottom edge to cut through the adhesive.

Do not remove the pick until the repair is complete, as this can cause the adhesive to reseal.

Heat an iOpener and apply it to the back cover's left edge for 2 minutes.

Apply a suction cup to the back of the phone near the left edge.

• Pull up on the suction cup with strong force to create a gap between the back cover and frame.
• Insert an opening pick into the gap, limiting insertion depth to 5 mm to avoid damaging internal components.

Do not cut past the camera shell and back cover — risk of damaging the plastic.

• Slide an opening pick along the left edge towards the bottom left corner to break the adhesive.
• Leave the pick in place to prevent resealing of the adhesive.

Apply heat from an iOpener to the right edge of the back cover for 2 minutes.

Apply a suction cup to the phone's back, near the center of the right edge.

• Pull up on the suction cup with strong force to create a gap between the back cover and frame.
• Insert an opening pick into the gap, but only for about 3 mm, as damage to the secondary interconnect cable is possible near this area.

Insert an opening pick at the right edge of the back cover.

• Slide it gently back and forth along this edge to separate the adhesive.
• Leave the pick in place to prevent re-adhesion.

Insert a right-edge opening pick into the top-right corner of the phone.

• Rotate the pick around the top-right corner.
• Limit insertion depth to 5 mm to avoid damaging internal components.

This procedure can be applied to other corners, but avoid the top-left where the rear-facing camera is located.

Position the top-most opening pick near the camera shell.

• For the left edge, repeat the process with a second opening pick.

Heat an iOpener until warm.

• Apply the heated iOpener to the camera shell.
• Leave the iOpener in place for two minutes.

Rotate the back cover counterclockwise to create a 5 mm gap.

• Only insert the pick up to 5 mm to avoid scratching the camera.

• Insert an opening pick into the created gap.

If this method does not work, proceed with the alternative method described in the next step.

Risk of damaging the plastic back cover. Proceed with caution.

• Slide two picks under the camera shell's corners.
• Move picks along bridge between camera shell and back cover to create gap.

Insert an opening pick between the camera shell and frame

Multiple rounds of heating may be required due to significant adhesive strength.

Apply heat as necessary and attempt to cut the adhesive with the pick.

Remove excess adhesive from the right side of the camera using your tool.

Be cautious not to catch the pick on the plate around the flash as it may become stuck.

Angle the pick downwards to avoid damaging surrounding components.

Align the opening pick's tip with your phone's flash.

• Slowly insert the pick, avoiding the flash's plate.
• The plate may feel like adhesive in resistance; angle the pick downward to prevent it from getting stuck.
• Slice the adhesive to the right of the camera.

Remove the back cover.

• If the back cover is stuck, slide a pick around its edges to separate it from the frame.

Power on your phone and test functions before reassembling, then power down completely before continuing.

Remove adhesive chunks with tweezers or fingers. Wipe away residue with high concentration (over 90%) isopropyl alcohol.

• If using Samsung custom-cut adhesives, follow the specific guide.
• If using double-sided tape, follow the specific guide.

Remove the motherboard bracket using a Phillips screwdriver.

• Remove five screws, each 4 mm long,
• Keeping track of their location for reassembly.

Do not fully remove the motherboard bracket yet.

• Use a pair of tweezers to gently lift and unclip the motherboard bracket from the frame.
• The bracket should still be attached to the wireless charging coil at this stage.

Hold the motherboard bracket out of the way with tweezers or your fingers.

• Use a spudger to pry up the battery press connector, carefully prying only under the edge of the connector.
• To reattach, align the connector and press down on one side until it clicks into place; repeat for the other side, avoiding the middle.

Misaligned connectors can cause pin bending and permanent damage.

Use a spudger to pry up the wireless charging coil's press connector, while keeping the motherboard bracket secure.

Peel off the wireless charging coil using your fingers.

• Secure the motherboard bracket screws first during reassembly to align the charging coil.
• Firmly press the rest of the coil into place, making sure it adheres properly.

• Remove the screws using a Phillips screwdriver.
• The screws are 6 in number, each with a 4 mm diameter.

Insert the point of a spudger into the notch in the top-left corner of the loudspeaker and pry up.

• The clips should release, allowing you to remove the loudspeaker.
• Once released, carefully lift out the loudspeaker.

Insert the flat end of a spudger between the primary interconnect cable's bottom press connector and the board, then gently pry it loose.

Insert the flat end of a spudger between the primary interconnect cable's top press connector.

Carefully pry upwards, then pull the connector away to complete the disconnection.

Remove the primary interconnect cable using either tweezers or your fingers.

Use the flat end of a spudger to gently pry up and release the secondary interconnect cable's lower press connector.

Insert the flat end of a spudger between the connector and the board.

• Pry gently upwards on the top press connector.
• The secondary interconnect cable will release.

Remove the secondary interconnect cable with tweezers or your fingers.

Remove the three 3.5mm screws using a Phillips screwdriver.

Locate the using a spudger.

• Pry up the daughterboard with the point of the spudger.
• Pull the up and away from the phone's bottom.
• If you encounter resistance, try gently wiggling the board while pulling until it separates completely.