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Fix iPhone SE Short Circuit and Restart Failed

Apple phones have always been one of the most popular smartphones in the world. Their functionality and hardware performance are also getting stronger with the iterative upgrade of models. But most people have a problem with mobile phones. 

The customer handed us an iPhone SE. The fault described is that the phone is very short and cannot be restarted.


   


After receiving the mobile phone, first use the mobile phone opening tool to remove the motherboard and feel the hot spot by hand. However, the position of the heating element is not obvious. 


Apply some rosin to the motherboard and reconnect the DC power supply. We still can't find the faulty part. The circuit is switched from the battery to the main power source through the conversion tube Q2300. 

Remove the Q2300 and measure the grounding resistance with a Fluke multimeter to see if there is a short circuit in the battery or mains.


A short circuit was found in the main power connection unit by value evaluation. Some rosin of rosin is again on the main power connection assembly.

When a single circuit is energized, C2331 melts immediately. 

It seems that this is the fault point to be repaired, so we use the QUICK hot air station to remove the capacitor C2331 and measure the resistance again. 

As a result, the resistance value is normal. Reinstall the Q2300 and power on the iPhone. The phone restarts

评论

  1. thanks for sharing. phone repair can be tricky. the fix is the best option if anyone is looking for top notch repair services.
    Ernst-August-Galerie Hannover, Ernst-August-Platz 2, 30159 Hannover, Germany
    (49) 15120983249

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