macbook pro won't power on

[Go-To Gordon]

I'm new to mac repair and thus far all the jobs I've taken have been software/osx issues until now.

Late 2011 13 inch macbook pro. He wasn't sure what osx. Probably whatever it came with.

Power button does nothing. Charger indicates it's charging, Battery indicator shows the battery is charged. User says sometimes it turns on (once in a few months). When it does it will run just fine until you shut the lid, then it's dead again. He said they left it open for 3 months and it ran fine, even when it went to sleep just not when you shut the lid. He then didn't touch it for a few months and when he tried it randomly cut on. After shutting down or closing the lid (not sure which he did, I think shut the lid) it's "dead" again. No spills reported (I asked), said the usb's worked fine as well.



Google pointed me in a few directions.

I do not have another power cord to try. Lights show green or amber depending what state it's in. It's the correct wattage original cord.

I've reset SMC

I've tried SMC bypass (With the magsafe disconnected press and hold the power button. While continuing to hold the power button plug in the magsafe connector. Continue to hold down the power button for 5 to 10 seconds. Release the power button and wait a couple of seconds. Now press and release power button)

Tried a pram/nvram but it's not powering on.

Tried unplugging the battery.

Tried with hard drive disconnected. Connected my external with Yosemite, still nothing. Pulled his data off via parted magic on my bench machine and checked smart.

Tried one stick of ram at a time.

Checked usb ports for shorted/bent pins. Pins looked fine but very dirty/dusty in there. Canned air didn't do much.

Checked logic board for damage (see pics). Cleaned all dust etc. No clear liquid damage but as you can see there is one spot that doesn't look so good!

So if it is the "burnt" looking spot how does that explain it working for 3 months straight as long as it was never shut down or the lid shut? And it came back to life briefly as well. Hasn't turned on once for me.

The other side of the board, on/near that spot are these two capacitors.

I've read about trying to "jump start" it. I do not see the solder points where they should be and I'm not winging it! I've also read about shorting pin 5 and 29 on the keyboard but haven't tried that.

 

[NYJimbo]

It does look like some kind of contaminant on the board. The pads circled in blue and the diodes (?) just south of the MAXIM chip and some other areas look like there was a spill of some sort. The flip side of the board with those cans also look like something is on the board. Circuits to the left of it don't look so good as well as one of the legs on the first coil (left). Maybe its just the photo or the lighting but are you fairly certain there is no spill damage ?

 

[Go-To Gordon]

It was very dirty from dust, dog hair etc so it was hard to tell. I cleaned all the dust/dog hair etc and as far as I could tell there wasn't. There was one spot I questioned but it looked like some sticky residue from the adhesive or something.

In your opinion would it be worth trying to clean the damage?


Edit: I agreee it looks like something around that chip. Gonna take another look and see if it's just the pic.

 

[NYJimbo]

Check about an inch or two all around your blue circle ( and the other side of the board) and look for ANY oxidized copper (green) on chips, circuits, traces, pads, if you see it then its likely a spill or water damage from heavy moisture (rain).

If its totally dead right now you cant really hurt it too much by cleaning it.

But I would GENTLY clean that blue circled group of pads and see if you get shiny clean copper. If you do then it could just be a non-corrosive build up or something. If you get brown or green or dull stuff then its corroded or oxidized.

Mac motherboards use so many tiny BGA/SMD chips that if they get a spill they will corrode or oxidize underneath and you cant tell whats going on without removing them first.

So if it was me I would try to determine if you have a decent spill with corrosion and if so I wouldn't put too much more time into it.

 

[Markverhyden]

What about the PRAM battery?

 

[Go-To Gordon]

late 2011 doesn't appear to have a dedicated pram battery.

 

[Markverhyden]

In that case it's supported by a capacitor or the battery itself. The symptom you described matches PRAM battery issues I've seen in the past. Namely the machine will turn on sometimes and run fine once it's turned on. But when shut down it will not turn on.

So my guess is it's the logicboard since the battery is taking a charge. I agree with NYJimbo, clean up the corroded areas you can see. No change, time to move on. You can get "refurb" logicboards but I would be very careful. Apple does not participate in that process so the people doing this are not getting OEM support from Apple or Foxconn.

 

[Go-To Gordon]

Cleaned that spot and one other I saw for sure. The one that is circled still shows some green.

It booted right up on the first try. Not expecting it to last but it's the first time since I got it yesterday.

 

[NYJimbo]

Cleaned that spot and one other I saw for sure. The one that is circled still shows some green.

It booted right up on the first try. Not expecting it to last but it's the first time since I got it yesterday.

Clean it up, get paid and get it the hell out of your shop.

ps- I wouldn't offer much of a guarantee on this one.

 

[Go-To Gordon]

no doubt

edit: shut the lid (only for a second) and it came back. rebooted as well. haven't done a full shut down and start yet.


btw this has only been on battery so far.

 

[anti]

For "jump starting" it's usually two solder points slightly more raised looking then the rest. You can use a common or tweezers to short them.

 

[Markverhyden]

Cleaned that spot and one other I saw for sure. The one that is circled still shows some green.

It booted right up on the first try. Not expecting it to last but it's the first time since I got it yesterday.

Great to hear!

 

[Go-To Gordon]

Well all was well. after multiple reboots I got confident enough to do an actual shut down. Now it won't power back on....

 

[Markverhyden]

Bummer. How did you clean those areas? Pencil eraser? Also did you flash the PRAM when you were rebooting?

 

[Go-To Gordon]

I used lint free foam swabs and 99% isopropyl alcohol. Same as I use to clean thermal paste.

I was under the impression that to reset pram it needed to be done from a complete shutdown. That is what I was about to do.

 

[Markverhyden]

Pencil eraser, soft gum, is an old standby for cleaning off surface corrosion on PCB's. Used it all of the time when I worked offshore. And you can flash pram on a reboot. Just start the reboot process and when the desktop goes away hold down the keys. I always let it chime 2-3 times.