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Model A1286. Released February 2011 / 2.0, 2.2, or 2.3 GHz Quad-core Intel Core i7 Processor

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MacBook A1286 momentarily works after an SMC/PRAM reset

As some of you are aware, the A1286's were plagued with GPU issues. Logic board has been replaced some years back, and has worked up until now. I attempted an SMC reset (the only way it will turn on), fans run at high speed long enough to enter the password before showing a horizontal line across the screen and shutting down. The only way to get it to power on is by that method. Attempted to replace battery, to no avail. The magsafe even recognize it. Here is the attempts I have made to revive the computer as follows.

  • SMC reset
  • PRAM reset
  • Replaced battery
  • Unplugged fans during boot
  • Replaced logic board entirely

Even with a new logic board, it still will not power on without resetting the SMC, to which it does what it was doing before; boots with fans at high speed long enough to see the login, or even shuts down during boot with a horizontal line across the screen.

I've tried everything in the book as far as I have had experience with and still cant figure it out.

Any help is GREATLY appreciated.

Ответ на этот вопрос У меня та же проблема

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EDIT: RAM!!!!! RAM will cause horizontal lines!! Try a new ram stick or try them one by one in different slots.

DO NOT put it in the over like the previous answer suggests...

DO NOT clean it with alcohol. It is 100% useless in this case.

How long ago did you replace the board? These boards suck. You probably got another bad one.

Unplug everything but the dc in board and the screen cable (Including battery) plug the charger in. Does it work? If so. narrow it down. Start plugging things in one by one and see what screws it up.

If it still does it with everything unplugged. New board. Get a 820-3330. It will work and wont die. You may have to modify the LVDS connector a little but that's it.

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This is a new one on me. Do you have any supporting documentation?

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@mayer What part of my answer? Replacing the board with a 2012 3330 series board, or the RAM? If so with the RAM, I do not have documentation, however I have seen it before.

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@tcrs_circuit RAM causing horizontal lines

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@mayer It's just something i've seen and heard of. He replace the board 2 times. Both boards have had the same symptom set. What common components do you transfer over to the new board? RAM. When the system is on the Intel iGPU , it will use the system RAM and not the dedicated VRAM as well. The whole high fan speed etc is symptomatic of something messing around with the CPU, and what has very close communication with the CPU? RAM

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Just remember the 820-2915 board will not turn on without smc_batlow_L. ie it needs a battery with sufficient charge connected else it won't turn on. Or you can jumper smc_batlow_L to 3.3v.

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Hi Joseph,

I had a a1286 do something similar after pulling my hair out for hours, I decided too bake the board in an oven to fix any cold soldering joints.

Here are the steps I took:

Removed logic board

Cleaned logic board with 100% Alcohol

I then added No clean Flux to the components on the board

Then I baked the Board for 30 min at 385 degrees Fahrenheit

Let it cool in the oven till oven is cool to touch

Then I did it one more time

Cleaned the board

reinstalled the board and whatever issue there was it fixed.

I saw that you put in a new logic board new logic boards can still have bad solder joints.

The Fact that resetting the SMC and PRAM fixes it temporarily seems to point out an issue with one of the chips so maybe oven method will help.

Hope it helps

TCCTech

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Lol, I am not sure if that was a Tech support or Martha Stewart Natchos

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You claim to be a tech and put it in the oven? I could see doing a reflow using a hot air work station where you can control solder flow, but putting it in the oven drops you down to being a complete amateur.

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