Use this guide to replace the I/O daughterboard in your Samsung Galaxy S8. Components that would warrant replacement of the daughterboard include a damaged USB-C connector or microphone.

This guide involves removing the rear glass cover, you will need replacement adhesive to reattach the back cover to the phone.

Before disassembling your phone, discharge the battery below 25%. The battery can catch fire and/or explode if accidentally punctured, but the chances of that happening are much lower if discharged.

Video Overview

  1. We recommend that you clean your microwave before proceeding, as any nasty gunk on the bottom may end up stuck to the iOpener.
    • We recommend that you clean your microwave before proceeding, as any nasty gunk on the bottom may end up stuck to the iOpener.

    • Place the iOpener in the center of the microwave.

      • For carousel microwaves: Make sure the plate spins freely. If your iOpener gets stuck, it may overheat and burn.

  2. Heat the iOpener for thirty seconds.
    • Heat the iOpener for thirty seconds.

    • Throughout the repair procedure, as the iOpener cools, reheat it in the microwave for an additional thirty seconds at a time.

    • Be careful not to overheat the iOpener during the repair. Overheating may cause the iOpener to burst.

    • Never touch the iOpener if it appears swollen.

    • If the iOpener is still too hot in the middle to touch, continue using it while waiting for it to cool down some more before reheating. A properly heated iOpener should stay warm for up to 10 minutes.

    • Remove the iOpener from the microwave, holding it by one of the two flat ends to avoid the hot center.

    • The iOpener will be very hot, so be careful when handling it. Use an oven mitt if necessary.

    • Opening your phone will compromise its waterproof seals. Have replacement adhesive ready before you proceed, or take care to avoid liquid exposure if you reassemble your phone without replacing the adhesive.

    • Apply a heated iOpener to a long edge of the S8 for about 2 minutes.

      • You may need to reheat and reapply the iOpener several times to get the phone warm enough. Follow the iOpener instructions to avoid overheating.

    • A hair dryer, heat gun, or hot plate may also be used, but be careful not to overheat the phone—the OLED display and internal battery are both susceptible to heat damage.

    • As you're waiting for the adhesive to soften, move on and read the following step to get an idea of where to pry.

    • In the following steps you will be cutting through the adhesive around the edge of the rear glass panel.

    • The adhesive on the rear case is laid out as seen in the first image.

    • The prying pattern as seen from the outside of the phone is as follows:

      • Thick portions of adhesive

      • Thin areas of adhesive

      • Avoid prying here, to protect the fingerprint sensor.

    • Once the back panel is warm to the touch, apply a suction cup as close to the heated edge of the phone as you can while avoiding the curved edge.

      • The suction cup will not make a good seal on the curved portion of the glass.

      • If the phone's back cover is cracked, the suction cup may not stick. Try lifting it with strong tape, or superglue the suction cup in place and allow it to cure so you can proceed.

    • Lift on the suction cup, and insert a halberd spudger, or opening pick, under the rear glass.

      • Due to the curved glass, you will be pushing up, rather than inserting parallel to the plane of the phone.

    • Once you have the tool firmly inserted into the glass, reheat and reapply the iOpener to soften the adhesive.

    • Slide an opening pick or the blade of a Halberd spudger down the side of the phone, separating the adhesive.

    • Go slowly so that the tool doesn't slip out of the seam. If cutting becomes difficult, reheat and reapply the iOpener.

    • Repeat the previous heating and cutting procedure for the remaining three sides of the phone.

    • Leave an opening pick on each side as you continue to the next to prevent the adhesive from resealing.

    • The fingerprint sensor cable connects the phone to the rear glass near the main camera. The cable is very short and should disconnect as the rear glass is removed.

    • As you lift the glass, peek in to be sure the orange cable with a blue connector has disconnected.

    • Use the opening picks to slice through any remaining adhesive and open the phone slightly.

    • If the fingerprint sensor cable seems snagged or stays taut do not open the phone any further. Disconnect the connector with the point of a spudger before proceeding.

    • During reassembly, in order to reconnect the fingerprint sensor cable, first angle the back cover into position until the cable connector lines up perfectly over its socket. Then, use the flat end of your spudger to gently snap the connector into place by pressing it straight down.

    • Remove the glass from the phone.

    • To reinstall the back cover:

      • First use tweezers to peel away any remaining adhesive from both the back cover and the phone's chassis.

      • Then, clean the adhesion areas with high concentration isopropyl alcohol (at least 90%) and a lint-free cloth. Swipe in one direction only, not back and forth. This will help prep the surface for the new adhesive.

      • Be sure to turn on your phone and test your repair before installing new adhesive and resealing the phone.

      • Replacement adhesive comes in a pre-cut sheet to match the exact contours of the back cover. If that's not available, you can use a high-bond double-sided tape, such as Tesa 61395. Be aware that this leaves gaps that are vulnerable to liquid intrusion.

      • After installing the rear cover, apply strong, steady pressure to your phone for several minutes to help the adhesive form a good bond, such as by placing it under a stack of heavy books.

    • If desired, you may reinstall the back cover without replacing the adhesive. Remove any large chunks of adhesive that might prevent the back cover from sitting down flush. After installation, heat the back cover and apply pressure to secure it. It won't be waterproof, but the glue is usually more than strong enough to hold.

    • Remove eleven 3.7 mm screws.

    • Remove the NFC antenna and charging coil assembly.

    • Remove three 3.7 mm Phillips #000 screws.

    • Remove the loudspeaker assembly.

    • Insert a SIM card opening tool into the small hole on the left side of the top edge of the phone.

    • Press to eject the tray.

    • Remove the SIM card tray from the phone.

      • When reinserting the SIM card, ensure that it is in the proper orientation relative to the tray.

    • Use the flat end of a spudger to disconnect the battery connector.

    • Although the battery is not shown in the next steps, there is no need to remove it for this guide. Just disconnect the battery and you're good to go.

    • Use the flat end of a spudger to disconnect the sensor array connector.

    • Use the flat end of a spudger to disconnect the front-facing camera connector.

    • Use the flat end of a spudger to disconnect the display and digitizer connector.

    • Use the point of a spudger to disconnect two antenna cables that connect the motherboard to the daughterboard.

    • Use the flat end of a spudger to disconnect an antenna ribbon cable that connects the motherboard to the daughterboard.

    • Use the flat end of a spudger to lift the motherboard and disconnect it from the daughterboard.

    • Lift the motherboard out of the phone.

      • Careful not to snag the battery connector if you chose not to remove the battery.

    • Remove one 3 mm Phillips #000 screw.

    • Use the point of a spudger to disconnect the headphone jack connector.

    • Insert the point of a spudger in between the headphone jack and the board, against the corner of the jack closest to the ribbon cable.

    • Use the spudger to gently pry the headphone jack out of the board.

    • Remove the headphone jack.

    • Use tweezers to pull the two antenna cables out of their slot next to the battery compartment.

    • Use tweezers to continue to remove the antenna cables from their slot.

    • Remove five 3 mm Phillips #000 screws.

    • Gently fold the motherboard connector toward the bottom of the phone and out of the way of the antenna ribbon cable.

    • Use tweezers to gently peel the antenna ribbon cable off of the side of the case.

    • Use tweezers to lift the daughterboard out of the case.


After reapplying adhesive, follow these instructions in reverse order to reassemble your device.

15 other people completed this guide.

Adam O'Camb

Member since: 04/11/2015

42,679 Reputation

127 Guides authored


iFixit Member of iFixit


108 Members

7,510 Guides authored

One Comment

Something you should add is that the battery temperature sensor is actually on the wireless charging coil. Unless you screw that part on, adding a new daughter board and plugging it in will result in the phone thinking the battery temperature is too low and thus it won't charge

Chinook Piroh - Reply

View Statistics:

Past 24 Hours: 26

Past 7 Days: 170

Past 30 Days: 705

All Time: 8,955