Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

DanielKYantis

macrumors newbie
Original poster
Feb 8, 2013
14
1
Austin, Texas
I can't believe I made such a stupid mistake!!! I just purchased a used MacBook Pro 13" 2010 and wanted a larger HDD. Broke it 30 minutes after I first got it!!!

I'm not completely new to repairs but I was in a hurry and picked up a metal tool to remove the battery connector (before replacing HDD) and shorted the soldering leads on the board for the connecter...

The MacBookPro7,1 turned on and booted but VERY SLOW and kernal takes up 198% cpu usage and causes an unusable computer. In another forum I learned how to fix the kernal issue by moving a .kext file and that did work.

The Fan is at high speed all the time and the battery is not detected at all. The battery was 100% so i can still do various tests as needed. I am not able to boot on battery but I can boot with power plugged in.

The power light is green on the power adapter but I have an 'X' on the battery icon...

I have been kicking myself for hours now and after spending all night reading through forums I've decided to just ask how to trace the problem to the broken component.

I have tried the SMC reset and when I power on after the reset it says date is wrong... so i figure the reset worked. I checked the fuse next to the battery connector and I get about 12 volts on both sides.
 
If the +12V connection from the battery to the MBP is okay, what about the 0.0v line? You may have melted a circuit board trace. I don't know why you had to disconnect the battery to swap HDDs. As long as the MBP is off, there's no voltage present at the socket. Actually, SATA HDDs are hot swappable.
 
If the +12V connection from the battery to the MBP is okay, what about the 0.0v line? You may have melted a circuit board trace. I don't know why you had to disconnect the battery to swap HDDs. As long as the MBP is off, there's no voltage present at the socket. Actually, SATA HDDs are hot swappable.

Lots of instructions suggest removing the battery 'just in case', but no metal tool belongs anywhere near any of those connectors or anything. Those same instructions generally suggest a plastic spudger or just your fingertip to remove the battery connection.
 
  • Like
Reactions: SDColorado
when i changed the memory and hd the directions i read also said to disconnect the battery. I had the plastic tool though that came with a screwdriver kit to take it apart. I have to admit though I might have used a butter knife or something without even thinking had i not had the tool. when you look at the connector it just looks like a plastic cap.
 
OMG, I feel like such a noob! I totally agree that I really messed up. I was in a hurry and like 'this is easy' and ' I've done this a 100 times', but in fact I was
absolutely wrong to grab a metal tool!

Guys, this is not a matter of how I messed up, but how to fix it...

I already feel stupid enough... I also didn't know SATA was hot swappable. I just followed the posts here.

What is my best action now?
 
  • Like
Reactions: SDColorado
If the +12V connection from the battery to the MBP is okay, what about the 0.0v line? You may have melted a circuit board trace.

On another forum here I got the battery connector pinout:

1 +12V
2 +12V
3 +12V
4 SMBUS_SMC_BSA_SCL
5 SYS_DETECT_L
6 SMBUS_SMC_BSA_SDA
7 GND
8 GND
9 GND

Measuring from pins 1, 2 & 3 to pins 7, 8 & 9 I do get 12v with all combination.
I also get 12v to all those pins measured from any ground point or screw & from the fuse to the the ground pins...
I assume all those tracers are ok then.

Using analog meter so numbers are approximate
MagSafe is not connected, battery powered only...

From pin 1 to pin 4 = 12v
From pin 1 to pin 5 = pulse 2v to 9v
From pin 1 to pin 6 = 8.2v

From pin 9 to pin 4 = 1.3v
From pin 9 to pin 5 = 0v
From pin 9 to pin 6 = 3.4v

See image attached: when I shorted the pins it was on the pin 1 side to either the ground point to the right of pin 1 or around pins 3-6. I wish I could be more exact but I just grabbed a tool to pry up the connector and started towards the right side when I saw a VERY small spark. (I can't believe I did this!)
 

Attachments

  • image.jpg
    image.jpg
    2 MB · Views: 4,317
The problem is, it may be producing the correct voltage, but it might not be producing that voltage under load. For example, a dead car battery might still show over 12 volts but it'll dip below that once you turn the key to start it.

Also possible is internal electronics were damages, so the machine isn't able to 'communicate' with the battery, so it won't use it. Your MacBook won't just take any 12 volt connection it finds, it must be able to connect with that battery and it's internal electronics, including temperature sensors and the like.

Finally, worst case scenario is that you shorted or damaged the battery connectors actually on the logic board, but let's hope not.

I'd source a battery from a place with a decent return policy. I'd plug it in, see if it works, if it doesn't return the battery and cut your losses. If it does work, great! Oh and pick up a plastic spudger while you're at it. Fingertips do work but a plastic spudger is a nice tool, and won't short anything.
 
If you shorted +12v to pins 4, 5, or 6, you could be in trouble, with something in the logic board battery/charge control circuitry fried. A small spark is indicative of a higher resistance to ground, possibly through low voltage logic. If you had shorted the +12v to ground, directly shorting the battery, you would have had much more than a small spark, and the fuse would likely have opened.
 
If you shorted +12v to pins 4, 5, or 6, you could be in trouble, with something in the logic board battery/charge control circuitry fried. A small spark is indicative of a higher resistance to ground, possibly through low voltage logic. If you had shorted the +12v to ground, directly shorting the battery, you would have had much more than a small spark, and the fuse would likely have opened.

Agreed... It was a VERY small spark and low current. The more I think back on it the more sure I am that I either shorted +12v to 4, 5 or 6 or shorted across 4, 5 or 6 directly.

I'm betting I fried some logic parts on the SMBUS. How can I trace the circuit and find the problem? Does the battery have any logic in it?
 
Apple Service Diagnostic EFI 3S138 for MacBook Pro (13-inch, Mid 2010)

Apple Service Diagnostic EFI 3S138 for MacBook Pro (13-inch, Mid 2010)

ERROR - SMC IO failed
- T E S T F A I L E D -

Their has to be a fix for this. If I can figure out where the bad component is I can replace it. I know how to use a meter and I have soldered many tiny ICs...

But I can not trace the board without a schematic and references!
Who can help me with this? I read through the Apple Service Manual and there is no schematics!
 
Last edited:
Apple Service Diagnostic EFI 3S138 for MacBook Pro (13-inch, Mid 2010)

ERROR - SMC IO failed
- T E S T F A I L E D -

Their has to be a fix for this. If I can figure out where the bad component is I can replace it. I know how to use a meter and I have soldered many tiny ICs...

But I can not trace the board without a schematic and references!
Who can help me with this?

Looks like you shorted to one of the I2C (I squared C) busses. Pins 4 and/or 6. The battery is now unable to communicate with the System Management Controller (SMC).

There are 3 possibilities.

1) The IC in the battery is damaged. You could check this with another known good battery. This would be the best case since a new battery is about $50.

2) The signals are damaged somewhere in the path to the SMC. Possibly the pullup resistors. Not too bad but will require circuit board repair.

3) The SMC I2C interface is damaged. Worst case. Replacing the SMC is very very difficult. It is a BGA package with solder balls under the package. Requires special equipment to replace.

The starting point is to remove battery terminal and unplug magsafe. If you can get hold of a digital multimeter that is vastly superior to using an analog meter. Set the meter to measure resistance. Place the black lead on one of the screw points (ground) and place the red lead onto pins 4 and 6 in turn. Document those resistances and report back. I have some known good boards I can tell you the correct reading. If something has failed it will likely show up in this reading.

edit: Just noticed you said "From pin 9 to pin 4 = 1.3v". This is your problem. The I2C signals should measure 3.4V. So you can focus on pin 4.
 
Last edited:
from any ground point to pins 5 & 6 are open and to pin 4 gives me a very fast resistance and then goes open. It's to quick to see with my digital meter.
 
from any ground point to pins 5 & 6 are open and to pin 4 gives me a very fast resistance and then goes open. It's to quick to see with my digital meter.

Just measured one of my boards and it measures:

Pin 4 and 6: 55.7kohm
Pin 5: 9.65kohm

However pins 4 and 6 take about 20 seconds to stabilize on those readings since there is some capacitance in those circuits. I then powered up the board temporarily and after powering it back down noticed pins 4 and 6 reading in the 600kohm range. So i then drained those circuits to ground and was getting readings in the 70kohm range.

Bottom line however, is if you let the macbook sit for a while unpowered then it should stabilize down into the 50-70kohm range once everything drains down to zero V.

Given that you know which pin is damaged you can focus on that. Best to try a known good battery first. You may be lucky and just be a damaged IC in the battery.
 
Looks like you shorted to one of the I2C (I squared C) busses. Pins 4 and/or 6. The battery is now unable to communicate with the System Management Controller (SMC).

edit: Just noticed you said "From pin 9 to pin 4 = 1.3v". This is your problem. The I2C signals should measure 3.4V. So you can focus on pin 4.

Yes, I just rechecked pin 4 voltage with digital meter and it is +1.1v with battery and MagSafe plugged in with system off.

However, I do get +3.4v to the 'Power-On pads' and those pins do allow me to turn on system but only if MagSafe is connected.

So now I figure I need to backtrack pin 4 and look for the power drop.
 
Yes, I just rechecked pin 4 voltage with digital meter and it is +1.1v with battery and MagSafe plugged in with system off.

However, I do get +3.4v to the 'Power-On pads' and those pins do allow me to turn on system but only if MagSafe is connected.

So now I figure I need to backtrack pin 4 and look for the power drop.

That 3.4V is G3HOT and it is present whenever any power, either magsafe or battery, is connected. If that was not present your Macbook would be dead in the water.

I would start by looking at the protection diode and the capacitor indicated. Unfortunately it requires removing them from the board to see if the resistance returns to normal 50kohm to 70kohm.

Before you get to that point I would try a different battery.
 

Attachments

  • SMBUS_BATT_SCL.jpeg
    SMBUS_BATT_SCL.jpeg
    173.6 KB · Views: 14,608
It appears that we are backwards on what we call pin 1 and pin 9...:)
I think I see that pin 4 (as stated earlier for confusion sake) is G3Hot with serial data stream... I don't know what the SMBus is communicating but I wonder if I could bypass the voltage side with a jumper to G3H elsewhere? See attached image...

ok... so now I am over my head for sure. In the schematic I see the D6950 & C6953 but I have no clue how to reference those with the actual board...
 

Attachments

  • 1.jpg
    1.jpg
    74.9 KB · Views: 5,667
It appears that we are backwards on what we call pin 1 and pin 9...:)
I think I see that pin 4 (as stated earlier for confusion sake) is G3Hot with serial data stream... I don't know what the SMBus is communicating but I wonder if I could bypass the voltage side with a jumper to G3H elsewhere? See attached image...

ok... so now I am over my head for sure. In the schematic I see the D6950 & C6953 but I have no clue how to reference those with the actual board...

No. This is a serial bus communicating between the battery, charger, and SMC. It is not about the 3.4V DC voltage. Riding on that voltage is the data signal so do not short it. It will not fix the issue and may create issues.

I would pause now and get yourself another battery to try before jumping in too far over your head.
 
You're looking in the wrong place - 99% of the time the short will kill the battery's electronics - not the ones on the MLB.
 
ok, I can do that...

However, I have a question: with battery unplugged on AC only, I still only get +1.1V at pin 4 (the soldered contact not the battery connecter). Doesn't that indicate a board side issue rather than battery side?

Can I check the battery circuit? What should the values be?
 
ok, I can do that...

However, I have a question: with battery unplugged on AC only, I still only get +1.1V at pin 4 (the soldered contact not the battery connecter). Doesn't that indicate a board side issue rather than battery side?

Can I check the battery circuit? What should the values be?

Hmmm. Not good. That would suggest that the issue is either the charger IC or the SMC. But I would still try another battery.

Replacing the ISL6259 charger IC is a job for a board repair expert.
 
Well i'm in luck... BatteryPlus has this battery in stock close to me. They said I can bring my MBP with me and we can just plug in the new one and see if it solves my problem. If not I don't have to buy it!
http://www.batteriesplus.com/product/47008-COM12049A-Battery/548-0/6514-Notebook-Laptop-Batteries/439864-Apple/3136-0-MacBook/MacBook-Pro-13-INCH-Unibody-A1278.aspx

----------

Hmmm. Not good. That would suggest that the issue is either the charger IC or the SMC. But I would still try another battery.

Replacing the ISL6259 charger IC is a job for a board repair expert.

I still think my SMC is not getting proper voltage to the chip... The diagnostic error indicated SMC IO FAILURE not any battery issues (because it can't get battery info without SMC). If pin 4 is low voltage and it should directly connect to SMC and G3H then wouldn't it be logical to test voltage at the SMC chip or charger circuit?

Where would I check that voltage? Again, reading a schematic and finding the correct part on the actual board are two different things... I can read but finding it is harder.
 
Well i'm in luck... BatteryPlus has this battery in stock close to me. They said I can bring my MBP with me and we can just plug in the new one and see if it solves my problem. If not I don't have to buy it!
http://www.batteriesplus.com/product/47008-COM12049A-Battery/548-0/6514-Notebook-Laptop-Batteries/439864-Apple/3136-0-MacBook/MacBook-Pro-13-INCH-Unibody-A1278.aspx

----------



I still think my SMC is not getting proper voltage to the chip... The diagnostic error indicated SMC IO FAILURE not any battery issues (because it can't get battery info without SMC). If pin 4 is low voltage and it should directly connect to SMC and G3H then wouldn't it be logical to test voltage at the SMC chip or charger circuit?

Where would I check that voltage? Again, reading a schematic and finding the correct part on the actual board are two different things... I can read but finding it is harder.

That is very decent of them. Hopefully it solves the issue.

If it does not then you are looking at a repair that is best left in the hands of an expert. The SMC is a BGA package which requires special equipment to replace. The battery charger ISL6259 is a 28 pin QFN package that requires very good soldering skills, a good hot air tool, very fine tip soldering iron, and a microscope. I replace those but not without some difficulty.

You might be able to use one of those eBay repair services. Don't have any to recommend because I have never used them.

Good luck.
 
ok... so the replacement battery did not help...

Did I mention that the battery light meters don't work either?

I might just sell this MacBookPro7,1 with 250G HDD for parts as is.
It works on MagSafe just fine...
 
Last edited:
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.