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MacBook Pro Unibody - No Backlight - Logic Board Question

zixu said:
FuLL

Normally when gpu is separated, mbp shouldn't work on external screen also.

And there should be no reactions on keyboard lights when u press buttons and any chimes or screams. :D
Click to expand...

Hmm.. He didn't mention that it's working otherwise...but if you say so. Yes normally it shouldn't. I have one original air that showed picture only on external. Only GPU reflow helped.
 
zixu said:
Is it working the indicator when u press the button?
Click to expand...

Well the Battery is currently at 91% and still charging, so if I press the check button, all the led's scroll up to the last led (the one thats permanently lit), then it blinks the last led but when its finished blinking the led, all the leds go out (as normal) except the last led which stays lit.
 
FuLL said:
Hmm.. He didn't mention that it's working otherwise...but if you say so. Yes normally it shouldn't. I have one original air that showed picture only on external. Only GPU reflow helped.
Click to expand...

I've noticed that if you have chipset with enough graphic output capability they redirect it's output to external display, maybe because of its lower resolution.

Internal display is powered by the powerful graphic card:ati, nvidia.

Of course never laptops this days are with switchable graphics. But still when Ati/nvidia dies, its like corpse.

I had maybe 3-4 situations like this. But most of them was with detachable graphic cards. And i can tell you we receive more than 4 laptops per day with graphic issues. And when the summer hits France, they rises significantly. :sly:

Anyway reflow is always an option. I wouldn't try myself on mbp reball. :D
 
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healeydave said:
Well the Battery is currently at 91% and still charging, so if I press the check button, all the led's scroll up to the last led (the one thats permanently lit), then it blinks the last led but when its finished blinking the led, all the leds go out (as normal) except the last led which stays lit.
Click to expand...

I've never had chance to play with this battery checker. But its connected to motherboard with tiny connector with 6-8pins probably one of the pins (for this led) is not making proper connection. And its permanently lid.

This is the only explanation for me especially if it was working properly before.

It looks like its circuit is working properly if it recognizes and lights the rest.
 
Yay.. i got wled driver(stupidly ordered only one sample) and and i started operation with getting old one off.. took old tin out with solder wick. cleaned with wurth electronic cleaner and put some amtech paste on pads.

had to put the chip with magnifier glass.. it''s so tiny :D heatgun to ~300c and voila..

somehow managed to put it wrong way :eek: and when it removed broken moved one resistor.. putting that back was so hard that i almost dropped on the floor..

https://www.dropbox.com/s/zlnrv01hinbgmda/photo 4.JPG

i have to start all over now..Put new order to texas instruments this time 3 wled drivers. it takes only 2 days to get them with fedex(to finland)
 
I know its extremely hard to work with these tiny components. Even with good eye, its still hard and they don't wanna solder easily. And this black board is not helping at all.
I was using a lot flux. I'm using flux pen. Also u can use capton tape to cover the small components. R's video will be helpful, several posts above.

I had succ. on the 2nd one. Hope you will too.

Of course at the end there will suspicion. Is it soldered properly. :screwy:
 
Musicsoul78 said:
MacBook Pro 13.3 Core i5 Laptop MC700 (Feb 2011) No Backlight

fuse good
lvds good
wled Replaced

now what ?????

here are some pics

Thanks to you all who contribute. :apple:
Click to expand...

I now have the same situation.. replaced wled second time.. this time right way :) was there good pinouts for the lvds?

trying to buy spare logic board.. cannot always take gf's macbook and pop the hood... :D

EDIT:

got new "magnifying glass" and i watched everry place once again.. noticed some old spills that i couldn't remove earlier.. this time i got them away.. and guess what :D yes there's some loose connection still i know.. i'm gonna wait for the new lcd now and try with it first.. then i know much more :)

https://www.dropbox.com/s/fgpl9ydmxezebge/Photo 12.3.2013 19.54.37.jpg

EDIT2:

Got new screen.. backlight still not working how it should. it starts when i measure logic board so there is something still broken.. resistor or something. and the lower edge still shows that theres loose connection or something..
https://www.dropbox.com/s/5qh0k0cauf2t6sb/Photo 13.3.2013 16.23.23.jpg
 
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Succes!

https://www.dropbox.com/s/fonrjqkywdyi9dt/Photo 13.3.2013 17.46.54.jpg

No loose connections! there was old spills or something that made resistance to chips this area. I reflowed the whole are with liquid flux(rosin) and it washed and reflowed at the same time so now it should be clean :)

I think that the problem was F2117LP

https://www.dropbox.com/s/nt90zq96o502118/Photo 13.3.2013 17.47.14.jpg

EDIT: and OSX installing :D

https://www.dropbox.com/s/ngr6ozj931mp0ij/Photo 13.3.2013 18.25.13.jpg
 
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FuLL said:
Hi folks..

I have a problem with MBP early 2011. i have two of them and the other got liquid damage. Backlight flickering once in a while..

i tryed to measure voltages while computer on but somehow i managed to kill something and now screen shows stripes on it..:/

tryed screen with working logic board and got backligt with stripes :/

so i killed the t-con board of the screen and have wled faulty logic board :D

I ordered some wled samples and i'm going to buy a new screen from ebay... let's see after that.

Cheers.. very useful info here.
Click to expand...

recently did the same thing on a mpb 2011 matt screen...

so now it has a wxga instead oh well
 
Hi everyone :)

First of all, thanks for this wonderful thread.
And to come to the reason i joined the forum is because i have a macbook pro 13" mid 2010 with the same problem. It's from a friend of me and i am the last chance to revive it.

The problem: no backlight. He puked on his laptop. Yuk
The thing didn't work at all, and it took 3 weeks till i received it. After cleaning the logic board, the macbook did start as normal, except the backlight. There was one thing what isn't normal in my opinion..

In all the pictures i saw, i think this should be the same mbp as mine (photo from earlier in the thead)
2zgg1o5.jpg


And this is how mine is..
2mq412v.jpg


Btw, the owner brought the mbp to an apple store and they said it would cost 1200 euro to fix this one.. probably they'll replace the logic board, or even give him a complete new mac from the previous generation

Already thanks :)
 
macattack600 said:
Needing some help identifying this component left of the wled driver it's in bad shape. The P fuse here was previously worked on with jumper wire. I've taken the wire off and I get continuity from ground --from one side and not the other I suppose I need to work off that not just expecting to replace only the fuse is there a good way to go about testing the wled it's different from the other a1278 any tips?
Click to expand...

its a resistor could be 100nf or 10nf but i have not got a clue as i dont have a scematic or a matching logic board ... cmr data is your man or dadioh or zixu

----------
fjutrackx said:
Hi everyone :)

First of all, thanks for this wonderful thread.
And to come to the reason i joined the forum is because i have a macbook pro 13" mid 2010 with the same problem. It's from a friend of me and i am the last chance to revive it.

The problem: no backlight. He puked on his laptop. Yuk
The thing didn't work at all, and it took 3 weeks till i received it. After cleaning the logic board, the macbook did start as normal, except the backlight. There was one thing what isn't normal in my opinion..

In all the pictures i saw, i think this should be the same mbp as mine (photo from earlier in the thead)
Image

And this is how mine is..
Image

Btw, the owner brought the mbp to an apple store and they said it would cost 1200 euro to fix this one.. probably they'll replace the logic board, or even give him a complete new mac from the previous generation

Already thanks :)
Click to expand...


by default all mbp fro the same year should look the same.... how ever ive seen a few from hong kong that are completely different. same parts different layout...

replace 2a fuse and test for continuity?

----------
l.a.rossmann said:
I finally put my money where my mouth is and made a more descriptive video. It only took six months. :eek:

Here is a semi instructional video, to help familiarize people who are diving into QFN soldering to get their macbook working. Fast forward to 4:15 and there is a camera pointed straight at the board so you can watch the entire process. May all of you do better than me. :)

I forgot to mention in the video, the iron is a Hakko 936, and the rework station a Hakko FR-801. You can save a lot if you buy some Aoyue stuff, they have caught up big time.
Click to expand...

:D:D:D:D:D:D:D:D:
LISTEN UP PEOPLE
Louis has made an awesome video on how to solder a wled driver make sure to watch this as it will help everyone to know what they are up against.
http://rossmanngroup.com/soldering
:D:D:D:D:D:D:D:D::
 
Musicsoul78 said:
by default all mbp fro the same year should look the same.... how ever ive seen a few from hong kong that are completely different. same parts different layout...

replace 2a fuse and test for continuity?
Click to expand...

And where can i find it?
After a better look, i saw there are also other components different then the other. My board is: emc no: 2351. i don't see any component with a dot.
But after a lot of trying, the mbp does fail a lot of times with the startup and powered itself off each time. I think it's ready for the trashcan
 
grize said:
Please could I have some help locating the WLED on this board? It is from a MBP 15" early 2011 i7. Logic board p/n: 820-2915-B. Thanks
Click to expand...


Dear Grize,

May I ask you if you have schematics & Board view of this Logic board? 820-2915-B

I have your same LB and I can't get the green power led on the Magsafe adaper.. Could you help me somehow?

Thanks in advance
 
healeydave said:
Ok, I had a Macbook Pro only 6 weeks old that had backlight issues (Ref: Post 1007).

Unfortunately, the backlight failure resulted in burn-out damage through to the LVDS connector (the worst case scenario).
Fortunately though, I managed to get the unit repaired under warranty, so the Logic board and the LCD have been replaced!

I had noticed a peculiarity prior to the unit going for repair which I have not seen mentioned anywhere before and its come back with the issue still.
The last LED of the battery checker is permanently illuminated (see Pic) even when the unit is powered down.

I did think this was probably an issue on the Logic board, but as this has now been changed, I guess it must be something else and obviously missed by the repair technician.

Anyone seen this before or know what could be causing it!?!?
Click to expand...

Probably a faulty sleep sensor (which is what the LEDs are part of).
 
fjutrackx said:
And where can i find it?
After a better look, i saw there are also other components different then the other. My board is: emc no: 2351. i don't see any component with a dot.
But after a lot of trying, the mbp does fail a lot of times with the startup and powered itself off each time. I think it's ready for the trashcan
Click to expand...

do not trash it....

i will help you

okay first look at your picture carefully and you will see the tiny 2a fuse next adjacent to that resistor

on iphone
 
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fjutrackx said:
And where can i find it?
After a better look, i saw there are also other components different then the other. My board is: emc no: 2351. i don't see any component with a dot.
But after a lot of trying, the mbp does fail a lot of times with the startup and powered itself off each time. I think it's ready for the trashcan
Click to expand...

use the search function in this thread and use 2a fuse and you will find the link for a 2a fast acting fuse.

get at least 10 they are very cheap.

also buy some isopropyl and a tooth brush

remove the logic board and clean it thoroughly with the isopropyl and toothbrush .

once this is all done PM me and and i will guide you through the rest.

also remove the dc-in and give that a good scrub too

here is the location of your 2a fuse
 

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Hello,
I have a MacBook Pro Unibody 15" mid 2009 with 2,66GHZ Core 2 Duo.
It works all fine, but the backlight from the lcd is not working.
I tested a other LCD with an other LCD-Cabel, it is the same, at an extern display, the MacBook Pro works without problems.
Any Idea what it is?
thx for helping

Mark83 from Germany :)
 
Musicsoul78 said:
use the search function in this thread and use 2a fuse and you will find the link for a 2a fast acting fuse.

get at least 10 they are very cheap.

also buy some isopropyl and a tooth brush

remove the logic board and clean it thoroughly with the isopropyl and toothbrush .

once this is all done PM me and and i will guide you through the rest.

also remove the dc-in and give that a good scrub too

here is the location of your 2a fuse
Click to expand...
Thanks for reply. But i already saw the picture and a lot of others. That fuse isn't there. At least not on that location. The board has a slightly different layout :/. I don't see any component with a small dot on it like the one on the picture.

/edit
I found a picture from exactly the same board as mine with the same emc number. (https://forums.macrumors.com/attachment.php?attachmentid=334475&d=1333695517) If i look at it, mine is missing the fuse where the left arrow is pointing to, and that 74 thing i said before. Since it is blown away the repair seems to be hopeless to me :/

/edit2
Here is the picture of the missing stuff. The contacts are ripped from the surface of the board so the contact points you see are under the surface, and its just soooooo tiny which makes it impossible to solder with my tools. my finest point is only .8mm thin. (a metcal). I once tried a cell phone with this kind of problem and it was a disaster since the solder would go into the small hole.
 
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@Dadioh

Thanks for this thread. My friend's child spilled some water on his MBP, and it has the "no backlight" issue. Researching led me to this thread, and I told him I'd "try" to fix it. Initially it didn't even turn on until I took it apart and cleaned the board with alcohol. That led to having everything but the backlight.

So, after a couple of weeks (he took it to bestbuy who quoted $1400 fix), he gave it to me and said to see what I could do. Upon taking it apart this time, the fuse with the "P" on it just came off when I touched it (lightly). Obviously corrosion/rust took hold.

Now, it appears I have another little piece missing, and it looks like the one contact for the fuse is missing. I've attempted to clean it to no avail. You can see from the picture that the one contact is still dirty (and only half looks connectable), but the other one is dull, and doesn't appear to have any metal under magnification. Also, it appears that another little piece is missing as well (right next to it, in a line of similar little guys). It also appears that the leads for the cable my be damaged.

I was hoping you could take a look at this and give me your assessment. Thank you.

 
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