Apple iPhone 4 – How to replace the Vibration motor – Mobiles and smartphones repair and service

Apple iPhone 4

Before disassembling your iPhone, be sure it is powered off.
Your iPhone 4 rear cover may have either two #000 Phillips screws or Apple's 5-Point "Pentalobe" screws (second image). Check which screws you have, and ensure you also have the correct screwdriver in order to remove them.
Remove the two 3.6 mm Pentalobe or Phillips #000 screws next to the dock connector.

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

The panel will move about 2 mm.

Pinch the rear panel with your fingers and lift it away from the iPhone. Alternatively, use a Small Suction Cup .

Be careful not to damage the plastic clips attached to the rear panel.
If you are installing a new rear panel, be sure to remove the plastic protective sticker from the inside of the camera lens and the sticker from the large black area near the lens.

Remove the single 2.5 mm Phillips screw securing the battery connector to the logic board.

Some devices may have two screws, one of which holds down the contact pad which is located above the screw indicated in red in the photo.

Use a plastic opening tool to gently pry the battery connector up from its socket on the logic board.

Pry from the top and bottom of the connector bracket -there isn't as much of an overhang on the sides, and you may damage the connector. Be very careful to only pry up on the battery connector and not the socket on the logic board. If you pry up on the logic board socket, you may break it entirely.
Remove the metal clip covering the antenna connector.

Use the clear plastic pull tab to gently lift the battery out of the iPhone.

You may need to use a plastic opening tool to loosen the adhesive under the battery.
Before reconnecting the battery connector, be sure the contact clip (shown in red) is properly positioned next to the battery connector.
Before reassembly, clean metal-to-metal contact. 
Perform a hard reset after reassembly. This can prevent several issues and simplify troubleshooting.

Use a SIM card eject tool or a paperclip to eject the SIM card and its holder.

This may require a significant amount of force.
Remove the SIM card and its holder.

Remove the following two screws:

Remove the thin steel dock connector cable cover from the iPhone.
Before reassembly, be sure to clean all metal-to-metal contact points on the dock connector cable.

Use an opening tool to gently pry the dock cable connector up off the logic board from both short ends of the connector.

Carefully peel the dock ribbon cable off the logic board and the lower speaker enclosure.

Do not use excessive force to peel the dock ribbon cable off the logic board. Doing so may tear the cable.

Use a plastic opening tool to pry the lower antenna connector up off its socket on the logic board.

Remove the 1.9 mm Phillips screw securing the bottom of the logic board to the inner case.

Remove the following five screws securing the Wi-Fi antenna to the logic board:

One 2.3 mm Phillips
Two 1.6 mm Phillips
One 1.4 mm Phillips
One 4.8 mm Phillips
When re-assembling, start off with replacing the 4.8 mm Philips screw first, then the 2.3 mm. This is to ensure there is no mix-up, and avoid rendering the LCD and digitizer useless.
Make sure to put the long 4.8 mm Philips screw back in correctly when reassembling. This is the ground for the Wi-Fi antenna and is often the culprit if you are having bad Wi-Fi reception after reassembly.

Use an iPod opening tool to slightly lift the top edge of the Wi-Fi antenna away from the logic board.

Use the tip of a spudger to pull the Wi-Fi retaining clips away from the inner frame.
Remove the Wi-Fi antenna from the iPhone. Make sure you don't lose the metal clips on the top of the cover. That's the primary reason for abnormal Wi-Fi performance after the reassembly.
Before reassembly, be sure to clean all metal-to-metal contact points on the connector. 

Use an opening tool to carefully lift the rear camera connector up off its socket on the logic board.

Remove the rear camera.

Remove the 2.4 mm Phillips screw.

Use the edge of a plastic opening tool to gently pry the following connectors up and out of their sockets on the logic board:

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)

Use a small flathead screwdriver to remove the 4.8 mm standoff near the headphone jack.
When reassembling the device, this standoff sets the height of the Wi-Fi shield.
If not torqued down, the shield will be above the plane of the frame and the back will not slide into place. 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.
When reassembling ensure that the small rubber spacer attached to the top of the motherboard is in place.
Without this part, the motherboard could damage the ribbon cables around it.

Carefully remove the logic board from the iPhone, minding any cables that may get caught.

Be careful not to damage the small gold prong (marked in red, near the top) as it's very fragile.
On reassembly, be careful not to trap the lower antenna cable beneath the logic board.

Use the edge of a plastic opening tool to lift the thin steel front camera retainer off the front camera.

Remove the front camera retainer.
During reassembly, position the clip's tabs on the outside of the receiving metal slots.

Carefully lift the front facing camera out of the iPhone.

It may be helpful to use tweezers to reinstall the front camera retainer.

Remove the following two screws securing the vibrator to the inner frame:

One 6 mm Phillips screw
One 1.4 mm Phillips screw
Remove the vibrator from the inner case.