More actions
| MacBook Pro A2251 no camera detected repair | |
|---|---|
| Device | MacBook Pro A2251 |
| Affects part(s) | Motherboard |
| Needs equipment | multimeter, soldering iron, soldering station |
| Difficulty | ◉◉◉◌ Hard |
| Type | Soldering |
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Problem description
Addressing issues with a MacBook (820-01949) not detecting the camera.
Symptoms
- Camera not detected
- Possible burned or exploded L8504 filter on TCON board
Solution
Repair Steps
Check L8504 Continuity
- Use a multimeter in continuity mode to check L8504 (Figure 1).
- Normal reading should be close to 0.01.
- If L8504 is blown or burned, proceed to the "L8504 blown or visibly burned repair steps" below.
Test with Known Good Display
- Verify camera function using a KNOWN GOOD display assembly.
- If the camera works with a different display, the original display might be faulty.
- Make sure to check L8504 before diagnosing the display issue.
Repair Steps
Camera Works with Known Good Display
- If camera works with a known good test display, replace the display assembly.
L8504 Blown or Visibly Burned
- Understand that L8504 failure indicates a catastrophic short within the TCON board of the display or a melted/corroded display cable/connector.
- Repair L8504 only after addressing the display issue, as L8504 might fail again if the display issue persists.
- When replacing L8504, address corresponding pad and trace damage.
- Use 36 or 37 AWG enamel coated copper wire for jumper wires due to webcam and ambient light sensor power requirements.
- Connect jumper wire from the input side of the filter (PP5v_G3S) to R5610 (Figure 2) or a suitable point.
- Apply conformal coating to jumper wire.
- Use a 120 Ohm ferrite filter rated for 1.5 amps (402 package size).
- After replacing L8504 and addressing trace issues, replace the display assembly or repair it by replacing damaged cables/connectors.
No Camera Function, L8504 Normal
- Attempt to restore T2/BridgeOs firmware via Apple Configurator 2 by entering DFU mode.
- Ensure your Mac is on the latest macOS version.
- Follow Apple's support article on reviving or restoring T2/BridgeOs firmware.
- If no camera function after firmware revive, and other causes are ruled out, U8504 might be faulty, or there could be trace/resistor issues between the camera connector/U8504 or between U8504 and the T2 chip.
- A hardware issue with the T2 chip might also cause camera detection problems.