iPhone 4S Power and Sensor Cable Replacement - iPhone 4s

Step 1 | Rear Panel

To start, ensure the iPhone's battery level is below 25%; a fully charged lithium-ion battery presents a fire or explosion hazard if damaged.
To prevent electrical shock or damage, ensure the iPhone is completely de-energized prior to starting the repair process.
Using a Pentalobe P2 screwdriver, detach the two screws measuring 3.6 mm located adjacent to the dock connector.
To prevent damage, ensure the driver is fully engaged with each Pentalobe screw before turning, as these screws are prone to stripping.

Step 2

Apply pressure to the back cover, directing it upwards against the device's upper boundary.
Expect a displacement of approximately 2 millimeters.

Step 3

Carefully detach the rear panel from the iPhone's back casing, taking precautions to avoid breakage of the plastic clips secured to the rear panel.
Carefully detach the iPhone's back cover.

Step 4 | Battery

Using appropriate tools, detach the battery connector from the logic board by unscrewing the specified fasteners.
Use a PH00 Phillips screwdriver to loosen a 1.7 mm screw.
Employ a PH00 Phillips screwdriver to loosen and remove a 1.5 mm screw.

Step 5

Gently disengage the pressure contact from the battery connector, ensuring it moves completely clear of its retaining location.
Carefully detach the pressure contact.

Step 6

Carefully disconnect the battery connector from the logic board by leveraging a plastic opening tool to lift it free of its receptacle.
Using the tool, gently pry up the connector's lower edge by inserting the tip into the gap between the loudspeaker housing and its metal cover.
To detach the battery connector, move it straight up away from the logic board; avoid any lateral pressure.
Avoid applying force directly to the battery connector's socket to prevent separation from the logic board, as it is secured by four tiny solder joints.

Step 7 | Reassembly tip

Ensure the pressure contact is correctly situated during reassembly, placing it atop the Philips screw post as indicated, with the gold contact oriented toward the battery connector.
To prevent wireless interference caused by oils from handling, thoroughly wipe the pressure contact using a cleaning agent like Windex or isopropyl alcohol.

Step 8

Using a plastic opening tool, gently slide the tip into the gap separating the battery from the iPhone's outer casing, positioning the tool near the device's lower edge.
Using the plastic opening tool, carefully detach the battery from the outer case by sliding the tool along its right side and gently lifting at multiple locations to break the adhesive bond.
To loosen a firmly adhered battery, carefully introduce a small quantity of isopropyl alcohol with a concentration exceeding 90% beneath its perimeter.
Allow approximately 60 seconds for the isopropyl alcohol to reduce the bond strength of the adhesive.
Carefully raise the battery using the flat, plastic tip of a specialized opening tool.
To prevent damage, avoid using excessive force when removing the battery; instead, if necessary, add additional drops of alcohol to dissolve the adhesive bond. Exercise caution and ensure the pry tool does not compromise the battery's structural integrity by puncturing or deforming it.
To prevent damage, ensure any residual alcohol solution is completely removed by wiping with a clean cloth or by permitting full evaporation before proceeding with the new battery installation.

Step 9

Carefully lift the battery away from its adhesive backing by grasping the visible, transparent plastic tab.
Exercise caution when drawing back the plastic tab, as excessive force may cause it to tear.
Disconnect the power source by detaching the battery.
Carefully detach the protective plastic packaging from the new battery by gently separating it from the ribbon cable.
Prior to installation, if the new battery's connector cable is not already formed, gently shape it to match the original cable's contours.
To confirm correct positioning during the new battery installation, briefly attach the battery connector to the device; after securing the battery with adhesive, detach the connector.
Following reassembly, execute a complete system reset to proactively avoid potential problems and streamline any subsequent diagnostic procedures.

Step 10 | Dock Connector Cable

Using appropriate tools, detach the logic board from the dock connector cable cover by unscrewing all screws that hold it in place.
Use a Phillips screwdriver to remove a single screw with a 1.5 mm head.
Use a Phillips screwdriver to tighten a 1.2 mm screw.
Carefully detach the metal cover protecting the dock connector cable.

Step 11

Carefully lift the dock cable connector from its corresponding socket on the logic board using the flat edge of a plastic opening tool.

Step 12

Carefully detach the dock connector cable from both the adhesive holding it to the logic board and the adhesive securing it to the speaker enclosure's side.

Step 13

Carefully lift the cellular antenna cable connector from its corresponding socket on the logic board, utilizing the edge of a plastic opening tool for leverage.
Carefully maneuver the cellular antenna cable, freeing it from the metal finger retainers secured to the logic board.

Step 14 | Rear Camera

Exercise caution when working near the rear camera flash; the plastic ring situated above it is prone to becoming dislodged if not carefully detached during the disassembly process.
Employ tweezers, a plastic opening tool, or a spudger to detach the external plastic ring.

Step 15

Using a screwdriver, detach the cable cover from the logic board by unscrewing the four screws that hold it in place.
Employ a Phillips screwdriver, size 2.7 millimeters.
Employ a Phillips screwdriver, sized specifically for 2.6 mm fasteners.
Employ a Phillips screwdriver, size 1.3 mm.
Employ a Phillips screwdriver, size 1.2 millimeters.

Step 16

Carefully disengage the cable cover tabs from the slots they occupy within the EMI shield on the logic board, utilizing the edge of a plastic opening tool.
Carefully detach the cable cover by gently prying upwards from the side closest to the uppermost edge, then separate it from the iPhone.

Step 17

Carefully lift the rear camera connector away from its socket on the logic board using the tip of a plastic opening tool.
Exercise caution during the upward separation process to prevent damage to nearby parts on the logic board.
Carefully detach the iPhone's rear camera assembly.
Before reassembling, verify the tiny rubber gasket located beneath the rear camera is correctly positioned.

Step 18 | SIM Card

Employing a SIM eject tool or a straightened paperclip, release the SIM card and its associated tray.
Expect considerable effort to be needed for this step.
Using the SIM tray removal tool or a small, straightened paperclip, carefully extract the SIM card and its associated tray from the device.

Step 19 | Logic Board

Disconnect the five cables located at the logic board's upper section, observing the specified sequence.

The flexible cable connecting the headphone jack and volume controls.
Connect the front camera’s ribbon cable.
The flexible ribbon cable connecting the display's touch sensor to the device's mainboard is referred to as the digitizer cable.
Connect the display data cable.
The power button cable is situated beneath the headphone jack/volume button cable, as illustrated in the second picture.

Carefully leverage the connectors of the cables upward from their sockets on the logic board using a plastic opening tool to avoid damage.
Exercise caution to avoid damaging the tiny, sensitive surface mount components while disconnecting the cables.

Step 20

Using a Phillips screwdriver, detach the grounding clip from the logic board's vicinity of the headphone jack by unscrewing the 1.5 mm fastener.

Step 21

Carefully lift the small grounding clip away from the logic board’s surface using the pointed end of a spudger.
Detach the grounding clip from the iPhone by holding it securely.
To prevent grounding problems, thoroughly clean all metal surfaces that will contact each other on the grounding clip—excluding the connector housings—using a solvent like Windex or isopropyl alcohol; this removes oils transferred from handling.

Step 22

Using the appropriate tool, detach the 4.8 mm standoff screw located close to the headphone jack.
To detach standoff screws, utilize a standoff screwdriver or a compatible bit.
If a dedicated tool isn't available, a small flathead screwdriver can be carefully employed; however, exercise heightened vigilance to prevent slippage and potential harm to nearby parts.

Step 23

Carefully separate the Wi-Fi antenna connector from the logic board’s corresponding socket using the tip of a plastic opening tool.

Step 24

Carefully remove the black tape that secures the screw located close to the power button, if it is present.
Using a Phillips screwdriver, detach the logic board by removing the 2.6 mm screw located close to the power button.
Exercise care while extracting the screw, as it secures the power contact, which is prone to detachment during removal.
During disassembly, be aware that a tiny rubber bumper is located beneath the screen and digitizer cables, specifically where they are disconnected near the Q-code; this component is prone to detachment from the logic board during removal or may become adhered to the cables and subsequently dislodge.

Step 25

Using the appropriate screwdriver, detach the logic board from the enclosure by unscrewing all listed fasteners.
Locate and remove a Phillips-head screw, sized at 2.5 millimeters, positioned close to the vibrator motor.
Use a Phillips screwdriver to remove a single screw with a 2.4 mm head.
Locate a 3.6 mm standoff positioned on the logic board's edge, closest to where the battery is situated.
Employ a standoff driver bit, attached to a driver handle, to detach the 3.6 mm standoff screw.
If a dedicated tool isn't available, a small flathead screwdriver can be carefully substituted; however, exercise heightened awareness to prevent slippage and potential harm to nearby parts.

Step 26

Gently raise the logic board, beginning at the speaker enclosure end, and move it horizontally, sliding it out from beneath the iPhone's top edge.
Carefully detach the logic board from the device enclosure.
To prevent grounding problems, thoroughly remove any residue from metal surfaces on the logic board—excluding connector pins—using a cleaning agent like Windex or isopropyl alcohol prior to reassembling the device. Finger oils can interfere with electrical conductivity.
A tiny rubber bumper, positioned on the logic board's upper edge at the point where the digitizer and screen cables exit the case, safeguards those cables from damage caused by bending. This component may adhere to the cables or detach from the logic board during disassembly; refer to step 22 for additional information.

Step 27

The grounding finger, a small component located close to the power button and the rear-facing camera, must be kept secure; it attaches to the printed circuit board via screws and is held in place by adhesive black plastic tape.

Step 28 | Front Facing Camera

Gently separate the metal component securing the front-facing camera from the iPhone's casing by carefully inserting the tip of a plastic opening tool along the seam.
Carefully detach the front camera securing clip.

Step 29

Carefully detach the front camera assembly.

Step 30 | Power Button

Using a Phillips screwdriver, detach the power button bracket from the outer case by unscrewing the two fasteners, each measuring 1.6 mm.
Because the display cables obstruct access to the right-hand screw and are susceptible to damage, handle them with caution.
Carefully displace the power button bracket a small amount, ensuring it clears the outer case.

Step 31

Carefully extract the power button from the iPhone using tweezers.
Ensure the power button is positioned correctly during reassembly; the metal loop must point downwards, and the outer edges should be uppermost.

Step 32 | Power and Sensor Cable Assembly

Carefully separate the earpiece speaker from the outer case by gently levering it away from the adhesive with a plastic opening tool.
Carefully separate the power button cable from the case by gently lifting it, as it is secured with adhesive.
Carefully extract the earpiece speaker from its housing within the outer case using tweezers.
Exercise caution during handling as the earpiece speaker and cable are bonded together; the cable is fragile and susceptible to damage if separated.

Step 33

Carefully disengage the top sensor assembly from the outer case by sliding the tip of a plastic opening tool between the two components.
Using careful, controlled force, detach the top sensor assembly from the outer case.

Step 34

Carefully detach the power and sensor cable assembly from the iPhone, ensuring no components are damaged during removal.
Carefully avoid misplacing the tiny clip secured to the upper sensor assembly.

Step 35 | Earpiece Speaker Assembly

Carefully separate the earpiece speaker from the foam adhesive with the tip of a plastic opening tool.
To avoid damaging the earpiece speaker if you plan to reinstall it, exercise caution and prevent separation of the foam adhesive holding it in place on the iPhone's housing.
Carefully detach the earpiece speaker assembly.

Step 36 | Power and Sensor Cable

Carefully slide the edge of a plastic opening tool between the power button contact and its plastic bracket to release the connection.

Step 37

Ensure the power and sensor cables are still connected.