Hy All,

I have an a1286 logic board (820-2330-A) and this is faulty (water damage). When I try to turn on, it turn on, but screen is black and logic board gives a beep code (3 long tones, 3 short tones, 3 long tones). I find that it means: Firmware restoration from CD in process. But firmware restoration CD isn't for this model.
Has somebody any idea?

Thank you!

Hi

Check all the board for the oxides damage.

Then if you find some damaged signal or power lines-reair it.
If no, clean it well and I thing everything will be OK.

Hi Duiesel,

I've cleaned the oxides damage, but it hasn't been good yet. I think it may be a bios problem, or not? I don't understand the code, because Apple didin't present firmware restoration CD for this type. But what does the code mean?

First of all, double check the board for oxidation.
I use these two:
http://www.radioshack.com/product/index ... Id=2104746
http://www.yaotek.com/store/ProClean-Fl ... P1908.aspx
Weird enough, these two in combo proved to clean off oxidation pretty well.

Then, try to read the EFI chip (I believe it's SST25VF032B) with a programmer (SP8-B) and verify it against a working dump (bunch of them here, ex: viewtopic.php?f=51&t=6547&p=65107&hilit=%2A820+2330+A%2A#p65107).
PS: Don't forget to change the board code in the EFI hex dump to yours before erasing and programming :)) (It's all the way at the end of the dump, the 17 digit ID)

Good luck!

Thank you! I checked these cleaners, but I can't buy in my country, I can order abroad these, but it will be very expensive. :(
I use PCC and isopropil alcohol for cleaning, I think these are good alternatives for yours.
So I have cleaned the board more times, but nothing happened. After I bought SPI programmer and I tried rewrite the EFI bios, but logic board doesn't work with the new dump. This is a mysterious fault for me. Maybe are the GPU, CPU or integrated RAM wrong?

Maybe there is any other stange behave?

Попробуйте прошивку для восстановления CD здесь:

http://support.apple.com/kb/HT2213

Имеет ли значение, если оно имеет Рами? звуковой картины что-то изменить?
Напряжение 3,4 V на флэш SST25VF ... ?