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Dacode34

macrumors newbie
Original poster
Jun 7, 2023
2
0
Hi all,

At the end of my rope on this one, so hopefully someone on this site can help-

I’ve got a 13” mid 2012 MacBook Pro running high sierra. Recently it has stopped charging my battery. I replaced the battery, the charge port, and the mag safe adapter to no avail. When the mag safe is attached, it lights up green and slowly pulses. The computer behaves like it’s on ac power at this time, but the battery does not charge. I am currently traveling through Jamaica and won’t be back state side for 2 months, so getting tech support is a tall ask. Has anyone else encountered this issue? All things point to a hardware problem, but I don’t know what else to check. So just to run down all the fixes I’ve tried-

Smc reset, changing battery charging behavior, firmware update, changed the charging port, changed the battery, changed the mag safe adapter.

Any help or direction that can be provided would be extremely appreciated. I’ve got 2 months of work left and no way to do it ☹️
 

tragicwinding

Suspended
May 23, 2023
55
39
Since you've replaced the usual suspects (battery, charging port, and MagSafe adapter), it could be a logic board issue, which unfortunately can be a bit tricky to fix without the right tools or expertise.

One more thing you might want to check, though it's a bit of a long shot, is whether there is any debris or dust in the MagSafe connector or port that could be interfering with the connection.

If you have access to another MacBook, you could also try swapping chargers to see if that makes a difference.
 

real_mon2

macrumors member
Mar 11, 2023
49
8
Windsor, Ontario, Canada
1) Does the magsafe head led ever go orange to denote that the battery is charging?
2) Do you have any charge left in the battery itself at this time? That is, if you use only the battery, does the laptop function normally?
3) From my point of view, you will need the special screwdriver set + multimeter to further diagnose this unit at the logic board level. The schematics are floating but will require some time to diagnose. If you have a local phone / computer repair shop that works at the component level, they should be able to assist. Continue the review here or open a fresh thread on badcaps.net laptop forum. Mention the same to the tech if they are not familiar with the unit.

Tools that are often required are:

screwdriver set to open the torx screws used by Apple / Foxconn
multimeter to review the voltage / resistance of the logic board components
hot air SMD gun + flux + soldering iron

These are very common tools to cellphone repair shops. Where in Jamaica are you? I may know a tech in your area from the badcaps forum but need to confirm.

Also, what is the history of this unit? Just decided to misbehave one day? Or was the battery replaced and then led to this fault? The reason being that often but not always, Apple logic boards feature a TVS ESD diode (it is a 2 line static discharge transient suppressor component with 3 legs). This device is intended to be self sacrificial and is there to prevent a surge from the tech / customer zapping the sensitive electronics. Often this ESD diode gets killed. Once this happens, the communication lines between the battery pack and the logic board will fail. Respectively, the logic board will then be unable to extract the required information from this power source and will treat as though the battery is absent.

Specifically, these are called the SMBUS (I2C) SCL and SDA lines and they are present on every battery pack used by Apple / Foxconn. Through these 2 lines, the logic board is aware the battery pack is docked and details such as # of charge cycles, etc. Each battery pack features a BMS board = battery management board that spits out this information. It is a quick test to confirm if this part (if present on the logic board model) is the fault. The part is less than $0.10 USD but requires the hot air tool to flux and remove and then ideally replace this part. We killed 3 days in locating this fault the first time - other techs gave up on this repair locally.

Update - based on the age of the unit, it is very possible that the original battery is just depleted and is unable to charge. There are flaky batteries on the market so be sure that the replacement battery is a known good one. Does Amazon service your region? With Amazon, you can return the product if it is not required.

Aside from the above, posting the ESD (electro discharge device) component which *may* be at fault.
 

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Dacode34

macrumors newbie
Original poster
Jun 7, 2023
2
0
Hi all, thanks for the responses. After further testing, I believe the fault is with the logic board, specifically the chip that handles the battery charging. I have found a local shop, so the computer is there currently being tested. Hopefully it’s something that can be repaired with a new chip, otherwise it’s eBay for a used a logic board. Will update when I hear back
 
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