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The March 2015 update of Apple's 13" MacBook Air features fifth generation Intel Core i5 and i7 processors, resulting in slightly increased performance and battery life.

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MacBook puts itself to sleep

I have a Macbook Air Early 2015 A1466 (EMC 2925) 661-02391 in the shop that randomly goes to sleep while using the Macbook. I have tried all the basics such as updating macOS. changing and disabling sleep settings, inserted another drive into the logic board, this resulted in the Macbook booting with the same issue. I also tried SMC Reset and NVRAM/PRAM Reset to no avail. The Macbook also goes to sleep in safe mode and recovery mode, the Macbook can stay awake for up to 30 minutes then decides to go to sleep and also will go straight back to sleep when woken up.

I have already guessed it’s likely a logic board issue and started to some minor probing with the multimeter in diode mode. After testing Pins 3/4 on the LCD connector I noted a diode reading of .468 which would indicate a bad U7701/LP8550 IC according to the following post: inverter board for a1466?

I am cautious to do anything like replacing the IC as I cannot see how a backlight IC would cause the Macbook to go to sleep. So before I go ahead and change the chip U7701, just off the diode readings alone, I thought I would ask you, fine people, for some advice on how to proceed. I am quite new to board diagnostics but have a basic understanding, Just tell me where to stick the probes and I can relay any readings :)

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Hold off replacing your logic board!

Instead, let’s get a better view of things, install this gem of an app! CoconutBattery take a snapshot of the apps main window and post it here for us to see Aggiungere immagini ad una domanda

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@danj I have attached a screenshot. I do not want to replace the logic board if it can be repaired with the hot-air station :) Maybe it is a bad battery but I can't see how other than its age of 2200+ days.

da

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So I would not normally answer my own question, but after replacing the main logic board the problems Persisted. So out of pure chance, I decided to disconnect the MagSafe charger board from the main logic board and now I have no more issues. So new Magsafe board has been ordered and will fully resolve these issues.

Again Thanks @danj for the help in troubleshooting, I have some very happy customers who have also opted to keep the new battery as the old one is still slowly dying :)

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Still need to do a bit more diagnostics here. Your battery is still running well. But we need to see if you have a short. Can you stop using your system and unplug it for a good 12 hours? What we want to see if the battery runs down (it won’t be much) note the Battery charge cap did it decrease a bit?

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@danj I have updated the screenshots with the laptop powered off for 13 hours as I got stuck on a call-out.

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@eazy_pc_repairs - Its on the edge, you need to consider the restart load into this as well.

Can you get some deeper history from your client. Did they has a liquid spill onto the system? Do they tend to spray a cleaner on the screen allowing the cleaner to drip down?

Did you inspect the LVDS connector on the logic board for corrosion as well as the reset of the logic board?

da

@danj Cheers for the prompt reply. They told me when they dropped it into me that it's never been near liquid and the board itself looks good other than an ultra-thin film of dust here and there. They said that it started happening now and then over a year ago and then it got to the point where it would leave every time they logged in. I managed to stop it logging out by disabling logout on sleep. But they have not used the MacBook for over a year now due to this issue.

I have also taken the logic board out and cannot see signs of water damage and nothing under the microscope either.

As for the screen they say they have only ever needed to wipe it down with a microfiber cloth.

The battery readings do seem odd how they have dropped over a period of the MacBook being turn off, is this a sign of a short or bad battery?

I did find references to bad batteries causing sleep issues somewhere on the internet.

If there are any other questions you want me to relay to the client then feel free to ask :)

da

@eazy_pc_repairs - If you have access to a good battery I would give that a try. That fact the system was sitting for a year is not good for the battery as the cells where likely charged instead of being at the neutral middle point of charge.

da

@danj OK, Would this issue still occur if I was to disconnect the battery and run of AC Adaptor or would I been right in thinking if it’s battery-related then disconnecting would solve the issue till we ordered a new one. I would rather be sure than start ordering parts blindly, even though my suppliers returns policy is fantastic :)

If the issue still occurs with the battery disconnect is there still a good reason to order a new battery to try?

Sorry for all the questions & thanks for your help, I am very grateful to not have to figure all this out on my own. The last question, would my diode readings for pin 3/4 on the LCD connector that usually indicate bad solder ball under LP8550 also cause the random sleep cycle?

da

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Jon Williams sarà eternamente grato.
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