I've had this computer from new, and it behaved great up until about this time last year. It started randomly shutting down, or some times just turn the display off. Restart needed to get it going again. Since I needed a reliable work computer I bought a 2015 MBP 15 to replace it and then I put it aside.

Now, I have Covid and so I have some down time to try to figure out what is going on. So I've played around with RAM, two batteries and booting from USB drives. Same problem. I did however manage to keep it running for longer this time, so I am writing this from the dodgy computer.... I hope it does not turn off before I'm done....

These are the shutdown causes it has logged.



...but I can't find any -2 causes listed anywhere. This is the best list of causes I have found so far. Anyone have some tips?

Bad solder joints on U8900 are a common source of intermittent video issues on there

The way I diagnose this (your mileage may vary) is to tap fairly hard on the board around the CPU with the unit running (U8900 is on the other side of the board in this area) if this causes you to loose video it is likely this is your issue

If you have a good soldering iron you can reflow the solder on the chip (You need to use good flux and add lots of leaded solder) however the board is a very good heatsink so this is actually much harder than certain YouTube repair channels make out! I tend to heat the chip with hot air while doing this to make the job easier

>> max1zzz said:

Bad solder joints on U8900 are a common source of intermittent video issues on there The way I diagnose this (your mileage may vary) is to tap fairly hard on the board around the CPU with the unit running (U8900 is on the other side of the board in this area) if this causes you to loose video it is likely this is your issue If you have a good soldering iron you can reflow the solder on the chip (You need to use good flux and add lots of leaded solder) however the board is a very good heatsink so this is actually much harder than certain YouTube repair channels make out! I tend to heat the chip with hot air while doing this to make the job easier Click to expand...

Would you happen to know a reputable source for schematics or at least a layout diagram of these boards? It's an 820-3330-B board and the only links I've found so far are quite dodgy, in my opinion... :)

>> max1zzz said:

Bad solder joints on U8900 are a common source of intermittent video issues on there Click to expand...

Is that the same as this issue? https://www.macrumors.com/2017/05/20/apple-ends-2011-macbook-pro-repair-program/

Is this a type of reflow that could maybe be fixed by baking the board in the oven? (Don't do this unless someone backs me up here, lol)

>> rjkucia said:

Is that the same as this issue? https://www.macrumors.com/2017/05/20/apple-ends-2011-macbook-pro-repair-program/ Is this a type of reflow that could maybe be fixed by baking the board in the oven? (Don't do this unless someone backs me up here, lol) Click to expand...

I don't think so. The main issue is that the computer seemingly at randomly shuts down. Some times, it simply drops video but I think what might actually be happening is a kernel panic or something like that. I have now enabled ssh and remote administration in an attempt to clarify. If I can ssh in to the computer, it could seem like there is a video related issue. I've seen some cases where the switching between the two graphics cards causes problems, but I can't really be sure.

That's one reason it would be handy to find out what the "Previous shutdown cause: -2" actually means as well :)

>> rjkucia said:

Is that the same as this issue? https://www.macrumors.com/2017/05/20/apple-ends-2011-macbook-pro-repair-program/ Is this a type of reflow that could maybe be fixed by baking the board in the oven? (Don't do this unless someone backs me up here, lol) Click to expand...

And just now, an hour later, I see you were responding to someone else... my apologies!

>> rjkucia said:

Is that the same as this issue? https://www.macrumors.com/2017/05/20/apple-ends-2011-macbook-pro-repair-program/ Is this a type of reflow that could maybe be fixed by baking the board in the oven? (Don't do this unless someone backs me up here, lol) Click to expand...

No, the GPU's themselves go bad on the 2011's, there are a few fixes that disable the dGPU on them (e.g: https://realmacmods.com/macbook-2011-radeon-gpu-disable/) it theory you can replace the dGPU but good luck finding a genuine supplier of the chip, most available are rebadged pulls

>> Alf Torp said:

Would you happen to know a reputable source for schematics or at least a layout diagram of these boards? It's an 820-3330-B board and the only links I've found so far are quite dodgy, in my opinion... Click to expand...

I'll drop you a PM :)

I've not done anything to this computer yet, but the issue seems to be getting worse. I was unable to start it at all this morning, apart from what you can see in this video
SMC problems?

Things (Tinks?) are not going well... I took the MBP apart and found the SMC. After removing the goop it had in the corners I found a cap and a resistor that seemed to be somewhat loose so I figured "Ok, I'll just make sure they are properly soldered on"...

...Guys, NEVER do anything - ANYTHING - if your brain starts inserting words like "I'm just gonna..." at the start of the thought. NO! Bad brain!

... so now I am stuck with a broken 100K resistor the size of pencil dust, and a computer that definitely does NOT work. I had a 100K smc laying around but... well, it's HUGE!

I mean...

No. Just no.

So I started digging around about and I found an old MBP 2.33 from 2006 I'm going to take the 100K resistor from, if I can find one.... Anyone have the schematics for that one floating around? It's an 820-2059-A board. Also... hot air station ordered. I'm not going to muck about with an ordinary soldering iron for this. I just notice how unsteady my hands are that way.

The U8900 fix (when properly executed) works wonders on video issues for the 2012/early 2013 15" retina. However, you appear to have a A1286 model. To my knowledge these did not have the same issues as the thin retina machines from that era. As was mentioned, the 2011 models had actual GPU issues (different from the U8900 chip).

>> Garrett said:

The U8900 fix (when properly executed) works wonders on video issues for the 2012/early 2013 15" retina. However, you appear to have a A1286 model. To my knowledge these did not have the same issues as the thin retina machines from that era. As was mentioned, the 2011 models had actual GPU issues (different from the U8900 chip). Click to expand...

The U8900 is an ISL6263C, would you happen to know if this is similar to the others?