1. Remove the SIM tray by finding the small black hole near the jack for the headphones using a paperclip. This is to avoid damaging it when you open the outer cover.

2. Find the two screws located on either side of the charging dock using the small Phillips screwdriver. Once you have removed them, you can start taking off the back cover.

3. Dont panic, but be careful nevertheless. The back cover may require some force and bending to remove it. Use the flat screwdriver to create a wedge between the black plastic cover and the front of the IPhone. Unless you have a plastic wedge, you will probably do some damage to the cover. Lift up from the back and slide the case forward to release it.

4. Carefully detach the ribbon cable that connects the case to the motherboard and set it aside to be reattached after you have replaced your battery.

5. Use the spudger to detach the LCD from the back panel by inserting it between the chrome ring and the front panel. Lift the display panel, and using the spudger release the black ribbon marked with a . Remember to release this black cable first to avoid shorting out the board. Proceed with disconnecting the other ribbon cables. The spudger can be used to disengage the white tab holding the cable. Remove the display panel and set aside.

6. To remove the motherboard, you need to locate and remove eight screws with the Phillips screwdriver. One screw should be located under a warranty sticker. Lastly, detach a ribbon cable marked and lift the motherboard out. There will be a ribbon connecting the board to the camera. Remove the camera from its housing in the back panel, but it will remain attached to the board.

7. Carefully disengage the board from the dock connector using the spudger. It should lift easily if all screws have been removed. Slide it out. The battery should be right in front of you.

6. Using the flat head screwdriver, gently pry up the old battery from the slot, avoiding contact with any of the connecting wires that lead to the system board. Typically, the wires are held in place with sticky glue, which you will have to remove using the flat head screwdriver.

7. With the wires unglued, use the soldering iron to detach the wires, starting from the right, from the connectors on the board. Take note of where the new battery wires should be placed. Be careful here. You can ruin your board with the wrong kind of pressure. Remove the old iPhone battery.

8. Your new battery should have three wires, one of which is encased in plastic to prevent touching the other wires and shorting it out. Connect the two exposed wires first with a soldering iron, and then the protected one last. Place the new battery on its slot.

9.Reconnect all the cables and screws of the motherboard, replace the camera, and attach the ribbons for the display panel. Your IPhone should power up automatically. If it fails to do so, restart the IPhone using the home button.

10. Once the IPhone powers up successfully, you are done and may replace the outer cover. Don’t forget to reinsert the SIM tray.

Hopefully, everything works fine and dandy. The above instructions only apply to first and second generation IPhones, and there are no guarantees that your IPhone will work after you have replaced the battery. Unless you have some experience with electronic repair or have a newer IPhone in the wings, then you should proceed with this operation with extreme prejudice.

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