iPhone 4 Logic Board Replacement

Back panel on your iPhone 4 has either two #000 Phillips screws or Apple's 5-Point "Pentalobe" screws. Make sure to check which screws are used; also make sure that you have the appropriate screwdriver in order to remove them.

Remove the two 3.6 mm Pentalobe or Phillips #000 screws next to the dock connector.

While reassembling the phone, we suggest you to replace the 5-point screws with equivalent Phillips screws. We have all the necessary tools and screws needed to replace the Pentalobe screws with Phillips screws.

Force the rear panel toward the top edge of the iPhone.

The panel will move about 2 mm.

Squeeze the rear panel with your fingers and lift it away from the iPhone.

2.5 mm Phillips screw that secures the battery connector to the logic board needs to be removed.

Sometimes it may happen that certain devices have two screws, one of them securing the contact pad which is located above the screw marked red in the photo.

Gently separate the battery connector from the ends closest to the top and bottom edges of the iPhone using an iPod opening tool.

Make sure to raise only the silver battery connector and not the black connector on the logic board. If you force the logic board connector, you might break it entirely.

Do not push against the contact clip.

Separate the contact clip from the iPhone.

Gently lift the battery out of the iPhone using the clear plastic pull tab.

When removing the battery with the plastic pull tab you need to be very careful. On some devices, Apple tends to use too much glue, making it almost impossible to remove the battery in this way (tab might break due to excessive force).

You could use the iPod opening tool for batteries that won't move, however you need to take extra care while doing so.

We suggest you to try to take the battery out from the right-hand side because no glue is used on this side.

Remove the battery.

Prior to reconnecting the battery connector, check if the pressure contact (marked red) is positioned next to the battery connector in the right way.

Before reassembly, use de-greaser (96% ethanol alcohol can also be used, but contacts must be completely dry when done) in order to clean all metal-to-metal contact points on the pressure contact as well as its contact point on the rear panel. The natural oils on your fingers may cause wireless interference issues.

Eject the SIM card and its holder using a SIM card eject tool (paperclip will do as well).

You might need a significant amount of force to do this.

Remove the SIM card and its holder.

Following screws need to be removed:

One 1.2 mm Phillips

One 1.6 mm Phillips

Now the thin steel dock connector cable cover should be removed from the iPhone.

Before reassembly, use a de-greaser to clean all metal-to-metal contact points on the dock connector cable cover. Wireless interference issues might be accidentally caused by the natural oils on your fingers.

Carefully pry the dock cable connector up off the logic board from both short ends of the connector using an iPod opening tool.

Peel the dock ribbon cable slowly off the logic board and the lower speaker enclosure.

You must not use excessive force to peel the dock ribbon cable off the logic board, because you might tear the cable.

Pry the lower antenna connector up off its socket on the logic board using an iPod opening tool.

1.9 mm Phillips screw securing the bottom of the logic board to the inner case should now be removed.

Five screws securing the Wi-Fi antenna to the logic board need to be removed:

One 2.3 mm Phillips

Two 1.6 mm Phillips

One 1.4 mm Phillips

One 4.8 mm Phillips

It is advisable to start off with replacing the 4.8 mm Philips screw first when re-assembling, then the 2.3 mm. This is to ensure there is no mix-up, and avoid rendering the LCD and digitizer useless.

When reassembling, make sure to put the long 4.8 mm Philips back in correctly. This is the ground for the Wi-Fi antenna and is often the reason for sometimes having bad Wi-Fi reception after reassembly.

Carefully lift the top edge of the Wi-Fi antenna away from the logic board using an iPod opening tool.

Pull the Wi-Fi retaining clips away from the inner frame using the tip of a spudger.

Remove the Wi-Fi antenna from the iPhone. Be careful not to lose the metal clips on the top of the cover where the 4.8mm screw attaches or the 4.8mm screw. Abnormal Wi-Fi performance after the reassembly may happen because of this.

Use a de-greaser to clean all metal-to-metal contact points on the connector cover before reassembly. Wireless interference issues may be caused by natural oils on your fingers. De-greaser should not be used for cleaning the connectors themselves!

Slowly lift the rear camera connector up off its socket on the logic board using an iPod opening tool.

Remove the rear camera.

Remove the small circular white sticker (warranty sticker and water indicator) covering the screw near the battery pull tab.

Hiding underneath the sticker is 2.4 mm Phillips screw, so remove it.

Carefully pry these connectors up and out of their sockets on the logic board using the edge of a plastic opening tool:

Digitizer cable (pry from bottom)

LCD cable (pry from bottom)

Headphone jack/volume button cable (pry from top)

Top Microphone/sleep button cable (pry from top)

Front camera cable (pry from top)

Remove the 4.8 mm standoff near the headphone jack using a small flathead screwdriver.

This standoff sets the height of the Wi-Fi shield removed in step 13, which you will notice while reassembling the device. If not torqued down, the shield will be above the plane of the frame and the back will not slide into place in step 2. The shield should be flush with the headphone jack.

When reassembling the motherboard, ensure that its edge sits under the circled standoff, otherwise the screws will not fit.

Make sure that the small rubber spacer attached to the top of the motherboard is in place during the reassemble. The motherboard could damage the ribbon cables around it without this part.

Taking care of the cables that may get caught, slowly remove the logic board from the iPhone.

The small gold prong (marked in red, near the top) is very fragile, so make sure not to damage it.