Dead A1278 (Early 2011) Macbook Pro?

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Thanks for your help. Unfortunately I haven't got a good microscope or something to give a detailed image and I still can't see any burned ICs to focus on, but I've attached a few files that might help.

And strangely enough the "burned" pins near the CPU are not PP1V05, but VCORE.

I know CPUs rarely fail, but I'm not sure what else it could be. My guess is something happened to dump a higher voltage into the rail. It could be a cap, but there are a lot of caps on that rail and I didn't think failed caps tested as a dead short.

Does anyone have a copy of the schematics of this logic board 820-2936-B version, looking for identification of the surface mount round inductor 330 in the first picture. No power on my Mac pro. thanks

[BCConnectionLLC]

Re: Dead A1278 (Early 2011) Macbook Pro?

Does anyone have a copy of the schematics of this logic board 820-2936-B version, looking for identification of the surface mount round inductor 330 in the first picture. No power on my Mac pro. thanks

Its L6995 Specs - 33UH-20%-0.44A-0.455OHM

Its the 3V42 Inductor where that voltage is made by U6990

http://www.megafileupload.com/1Fau/L...ic_diagram.PDF

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Its L6995 Specs - 33UH-20%-0.44A-0.455OHM

Its the 3V42 Inductor where that voltage is made by U6990

http://www.megafileupload.com/1Fau/L...ic_diagram.PDF

Thank you, greatly appreciated.

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Its L6995 Specs - 33UH-20%-0.44A-0.455OHM

Its the 3V42 Inductor where that voltage is made by U6990

http://www.megafileupload.com/1Fau/L...ic_diagram.PDF

BCConnection, would you happen to be able to point out where I can purchase this inductor. Not having much success finding one. I checked Mouser , Ebay Not sure if I know exactly what I'm searching for. Thanks for all your help in advance.

[dj_ricoh]

Re: Dead A1278 (Early 2011) Macbook Pro?

i rly hate that guy but i must recommend him
Louis Rossmann
the last macbook he fix there was no 3.3 and 5v

[BCConnectionLLC]

Re: Dead A1278 (Early 2011) Macbook Pro?

i rly hate that guy but i must recommend him
Louis Rossmann
the last macbook he fix there was no 3.3 and 5v

Lol Louis might be harsh but hes experienced and that matters a lot in this profession.

Best place to get replacement random parts is dead junk boards.

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Thanks, BC

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Lol Louis might be harsh but hes experienced and that matters a lot in this profession.

Best place to get replacement random parts is dead junk boards.

Anyone have any 820-2936B version dead boards for parts for sale?

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Lol Louis might be harsh but hes experienced and that matters a lot in this profession.

Best place to get replacement random parts is dead junk boards.

Anyone have any 820-2936B version dead boards for parts for sale?

[dellxps15]

Re: Dead A1278 (Early 2011) Macbook Pro?

Lol Louis might be harsh but hes experienced and that matters a lot in this profession.

Best place to get replacement random parts is dead junk boards.

yes luis is very experienced, but when he have to replace a bga, he still use the lead free solder....

Anyone have any 820-2936B version dead boards for parts for sale?

wich component do you need ?

[BCConnectionLLC]

Re: Dead A1278 (Early 2011) Macbook Pro?

Anyone have any 820-2936B version dead boards for parts for sale?

Ebay has been ok for me.

[BCConnectionLLC]

Re: Dead A1278 (Early 2011) Macbook Pro?

yes luis is very experienced, but when he have to replace a bga, he still use the lead free solder....




wich component do you need ?

BGA chips most of the time dont fail because of the solder joint under the body of the chip. They fail because of the solder joints under the actual processor wafer/silcon. The small connections that you cant get to.

[atsio]

Re: Dead A1278 (Early 2011) Macbook Pro?

When there is a short has nothing to do with balls

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

yes luis is very experienced, but when he have to replace a bga, he still use the lead free solder....




wich component do you need ?

The surface mounted 330 inductor listed in post #22,23,24. Thanks

[BCConnectionLLC]

Re: Dead A1278 (Early 2011) Macbook Pro?

When there is a short has nothing to do with balls

Wasnt saying it was. Was addressing the comment I quoted

[dellxps15]

Re: Dead A1278 (Early 2011) Macbook Pro?

The surface mounted 330 inductor listed in post #22,23,24. Thanks

u need it because it is broken or becouse it is shorted ?

if it's broken then yes, u need to replace it. if u have short, inductor is good.

for short, diode mode, gnd on metal part of usb, vga ecc ecc and red on side of inductor. if shorted, remove inductor and measure again if shorted. thjat's 3.42volt line that power many component on board. locate a short on that rail is very hard. u need power supply lab, put 3volt max and start from 0.500mah growing on a,d look for heating capacitors or component.

When there is a short has nothing to do with balls

you are right.

BGA chips most of the time dont fail because of the solder joint under the body of the chip. They fail because of the solder joints under the actual processor wafer/silcon. The small connections that you cant get to.

not properly right. most of the notebook fails are releted to the bad joint under the chip, infact a reflow or reball fix problem.
ofcourse there are chip that are dead, but in that case u will get a shorted inductor.

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

u need it because it is broken or becouse it is shorted ?

if it's broken then yes, u need to replace it. if u have short, inductor is good.

for short, diode mode, gnd on metal part of usb, vga ecc ecc and red on side of inductor. if shorted, remove inductor and measure again if shorted. thjat's 3.42volt line that power many component on board. locate a short on that rail is very hard. u need power supply lab, put 3volt max and start from 0.500mah growing on a,d look for heating capacitors or component.



you are right.



not properly right. most of the notebook fails are releted to the bad joint under the chip, infact a reflow or reball fix problem.
ofcourse there are chip that are dead, but in that case u will get a shorted inductor.

Need inductor because it is broken, fell off when I opened up my mac.

[dellxps15]

Re: Dead A1278 (Early 2011) Macbook Pro?

almost any macbook from 2008 going on have that inductor. just look for a dead board near you country. and look for a picture of both side to spot if present or not.

[rccrasher65]

Re: Dead A1278 (Early 2011) Macbook Pro?

Thank you for all your help!

[d.ferch]

Re: Dead A1278 (Early 2011) Macbook Pro?

hey i have 1 820-2936-b dead board. how much r u offering for the dead board? txt me if so

Dan
d.ferch@me.com
(805)732-3996