How to Fix MacBook Pro Won't Turn On Issue

MacBook users often say that the MacBook Pro Will Not Turn On. This is an annoying problem for those users who store large amounts of data and important files on MacBook. There are many reasons why MacBook Pro won't turn on, such as some third-party apps conflict with the MacBook when it is started. This problem may also be caused by a problem with the MacBook-related account. If you also stuck with the same problem, then you can follow the below example to repair this issue.

Here is a 13-inch MacBook Pro with won't turn on problem, the fault described is that the MacBook Pro display screen suddenly turns black during the normal use, after pressing the power button, it has no response, the MacBook Pro 13 A708 won't turn on anymore. Here, we are about to discuss some basic troubleshooting ways to solve the ‘MacBook Pro won’t turn on’ issue. So, you can perform the steps stated below:

Firstly, connect MacBook Pro to the power supply via Apple lightning cable, press the power supply on MacBook, the MacBook has no response, it keeps black.



Disconnect the power supply, use JM-P01 Toolkit to open the MacBook, remove the rear case, and then remove the MacBook battery. Now carefully remove the MacBook motherboard. After taking out the MacBook motherboard, we can smell a charred smell, we suspected that there are some components had been burned.

We need to find out the damaged components, put the MacBook Pro motherboard on the WL Aluminum Alloy Pad.

Check schematic diagram and PCB bitmap, there is a compound diode D6905, which is for generating PP3V3_G3H, the first 3.3V power supply.

Based on MacBook schematic diagram, we know that the L6995 and D6905 Inductors are related to this circuit.

Use Fluke 17B+ digital multimeter to measure the inductor L6995, the value tested is 342, which is normal.



Next, we need to measure the inductor D6905, there are 3 pins we need to measure, they were pin 1, pin 2 and pin 3. After measurement, only the value of pin 2 is tested normally, both pin 1 and pin 3 are abnormal. The pin 1 value tested is 97, and the pin 3 value tested is 0, which is shorted.

We need to remove the D6905. Put MacBook motherboard under the Trinocular Microscope, with the help of the QUICK 861DW hot air rework station and tweezers, we removed the D6905 smoothly.



Now, we need to measure the pin 1 and pin 3 again. The value of the pin 1 is 442, which is normal, but the value of pin 3 is 0, which is still shorted.

Check the MacBook schematic diagram again, we can see that the pin 3 of D6905 is connected to pin 2 of U6990.

Use QUICK 861DW hot air rework station to remove the U6990, and then use digital multimeter to measure the pin 3 of D6905 again, the value tested is 0, it's still shorted. What's the real problem?

We need to check schematic diagram, at this time; we noticed that pin 3 of D6905 also is connected to C6990 and C6991. Remove these 2 capacitors, and then measure the pin 3 again, now the data tested is normal.

Now, install the new U6990/D6905/C6990/C6991 back to the MacBook motherboard, after installation, use digital multimeter to test MacBook motherboard, all data tested are normal.

Assemble the MacBook, supply power to it, press the MacBook power button, after few seconds, the MacBook is turned on properly. Using it for a while, the MacBook display screen works normally, and other functions also works perfectly.

After performing the above steps, you will be able to start the MacBook as expected. Hopefully, above repair ways will help you to fix the issue. If you want to read more about similar topics, you can visit www.vipfixphone.com.

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