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The larger of Apple's MacBook Air laptops featuring dual microphones and 802.11ac Wi-Fi connectivity.

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A1466 MacBook Air 820-3437-B No green light on charger

Hello, I am trying to repair a A1466 macbook that has no light on charger.

I have identified that (LT3470AED U7090 U6990) most likely has a short due to heat being generated on that chip.

I have already gone through the effort to replace the chip but the issue persists, is there anything I can do to further locate the real issue on the board?

I believe there is probably an issue on the onewire circuit but I dont really have direction where I should move forward.

Thank you.

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Did you check the power rails? Why do you think the one wire circuit is bad?

While a warm chip maybe bad, it’s not the first thing I jump to. More often I see liquid damage as the root cause when I get a dead system.

As the MagSafe LED is not lighting leads me to checking the MagSafe connector first for dirt and bad connection contact. Did you try tracing the middle contact to the SMC logic.

I make a through inspection of the logic board on both sides looking for corrosion and/or burnt components.

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Hello,

After taking your suggestions, I reviewed the board. I have found that PPBUS_G3H voltage is reading .6V when this power rail should be around 8.55V. I checked F7140 fuse and was not blown. I used a new DC IN board to make sure it was not the cause. It is possible that there was liquid damage but found no corrosion or signs of liquid damage at least from just a visual inspection alone. The repair wiki indicates maybe a possible bad U7100 but I would like to make some more tests before going to purchase a new chip. If you have any pointers to offer I would be more than grateful!

Thank you!

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@migjav - Using a hot air station with some flux. See if reheating the solder joints help. Otherwise I would just replace the chip.

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