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MacBook Pro Unibody - No Backlight - Logic Board Question
- Thread starter Dadioh
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Right you are. It is 5V powering the Wifi. I was going from memory and thought it was 3.3V. The other thing to check is the common mode choke that leads to the data signals. That is the device just to the right with 4 leads (circled in my attachment). You should read almost 0 ohms across the device (north south). I have seen these guys blow open.
Attachments
Thanks for all the advice Dadioh. I checked the resistance between the choke and it was close to 0 , so that seems to be within spec. I have an extra airport card that I am going to put in just to rule out that.
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I replaced the airport card still no luck. I also checked the two capacitors to the right of the choke they have .5v coming in an 7mv coming out of them.
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I replaced the airport card still no luck. I also checked the two capacitors to the right of the choke they have .5v coming in an 7mv coming out of them.
Did you check to make sure there are no shorts between adjacent pins on the connector? Also make sure none of the pins is grounded that should not be.
The caps are usually reliable so I would not expect those to be the issue. Caps don't pass DC current so you expect different voltages on either side. If they are symmetrical (both have the same voltages) that would be a good sign since they are carry balanced signals.
I have had cables fail on me in the past so that is another possibility. But the fact that you had that inductor blown off the board suggests that the issue is with that part of the circuit.
Hello everybody,
Unfortunately, I'm another person with a liquid spill problem in my computer... this time with a glass of red wine.
This as happened more then one year ago, and since then I've been using my MBP 13.3 (mid 2009) throw a external display. After I went to the apple assistance, I conclude that there was nothing I could do, because the price they ask was just to much for me... And now I can see a little light in the end of the tunnel, because I saw this forum, and I'm prepared to give it a try.
In my case, the LED backlight doesn't work, but I can see a faint image in the display. Sometimes I even close the lid to put the computer to sleep, and I bring it back to life throw an external mouse, so the faint image turns off.
I read all the posts, and this week I'll start to perform the tests in the logic board. I would just like to know if someone have some information about the 30 pinouts of the LVDS cable.
I'll post some images of the internal disgrace...
Thanks in advance!!
Tiago Gonçalves
![IMG_3533.jpg]()
![IMG_3531.jpg]()
![IMG_3530.jpg]()
Unfortunately, I'm another person with a liquid spill problem in my computer... this time with a glass of red wine.
This as happened more then one year ago, and since then I've been using my MBP 13.3 (mid 2009) throw a external display. After I went to the apple assistance, I conclude that there was nothing I could do, because the price they ask was just to much for me... And now I can see a little light in the end of the tunnel, because I saw this forum, and I'm prepared to give it a try.
In my case, the LED backlight doesn't work, but I can see a faint image in the display. Sometimes I even close the lid to put the computer to sleep, and I bring it back to life throw an external mouse, so the faint image turns off.
I read all the posts, and this week I'll start to perform the tests in the logic board. I would just like to know if someone have some information about the 30 pinouts of the LVDS cable.
I'll post some images of the internal disgrace...
Thanks in advance!!
Tiago Gonçalves
Dadioh - Request
Hi Dadioh, I have sent you a friend request. I may have an offer for you if you are interested. This is regarding a 13" MB Pro
Hi Dadioh, I have sent you a friend request. I may have an offer for you if you are interested. This is regarding a 13" MB Pro
I have fixed this issue a few times by replacing the connector and LVDS cable. Assuming nothing else is bad in the backlight circuit you will need a new ipex 30 pin connector soldered to the board and a new LVDS cable which involves opening the LCD.
If you replace these and you still get no back light check for an open in the fuse. If the fuse is good the problem may be the WLED driver chip (that square one next to the lvds connector) also as I see some goo on the solder points.
If you replace these and you still get no back light check for an open in the fuse. If the fuse is good the problem may be the WLED driver chip (that square one next to the lvds connector) also as I see some goo on the solder points.
Hello everybody,
Unfortunately, I'm another person with a liquid spill problem in my computer... this time with a glass of red wine.
This as happened more then one year ago, and since then I've been using my MBP 13.3 (mid 2009) throw a external display. After I went to the apple assistance, I conclude that there was nothing I could do, because the price they ask was just to much for me... And now I can see a little light in the end of the tunnel, because I saw this forum, and I'm prepared to give it a try.
In my case, the LED backlight doesn't work, but I can see a faint image in the display. Sometimes I even close the lid to put the computer to sleep, and I bring it back to life throw an external mouse, so the faint image turns off.
I read all the posts, and this week I'll start to perform the tests in the logic board. I would just like to know if someone have some information about the 30 pinouts of the LVDS cable.
I'll post some images of the internal disgrace...
Thanks in advance!!
Tiago Gonçalves
Image
Image
Image
I Think I Killed My Board
Dadioh - I hope you have a moment to read this. I replaced the cable (used) and replaced the connector (new) on the board. I think by removing the original connector, I may have damaged the logic board by breaking away some of the contacts on the board where the connector pins solder to. I can't even see anything on the LED now.
Please tell me there is still hope.
Dadioh - I hope you have a moment to read this. I replaced the cable (used) and replaced the connector (new) on the board. I think by removing the original connector, I may have damaged the logic board by breaking away some of the contacts on the board where the connector pins solder to. I can't even see anything on the LED now.
Please tell me there is still hope.
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Dadioh - I hope you have a moment to read this. I replaced the cable (used) and replaced the connector (new) on the board. I think by removing the original connector, I may have damaged the logic board by breaking away some of the contacts on the board where the connector pins solder to. I can't even see anything on the LED now.
Please tell me there is still hope.
Can you post a picture of the damaged traces on the logic board. There is always hope
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Accepted. Sorry for the delay. I have not been on the forum for a while.
MacBook Pro 13 2009 no backlight
Hi all,
I also have no backlight on my 2009 mbp, but at least I know what caused it. While i was replacing the lcd i accidentally shorted power and ground pins on the lvds connector and then the backlight went out, but the display still works without a problem.
I hope this is just a blown 2A fuse form the picture below:
![attachment.php]()
I have measured the resistance across the fuse but i get no signal at all, and certainly not in megaohms or kiloohms.
Is it safe to short the fuse with a screwdriver tip just to see if it really is the fuse?
Thanks to anyone who could give me some clues on how to proceed.
Hi all,
I also have no backlight on my 2009 mbp, but at least I know what caused it. While i was replacing the lcd i accidentally shorted power and ground pins on the lvds connector and then the backlight went out, but the display still works without a problem.
I hope this is just a blown 2A fuse form the picture below:
I have measured the resistance across the fuse but i get no signal at all, and certainly not in megaohms or kiloohms.
Is it safe to short the fuse with a screwdriver tip just to see if it really is the fuse?
Thanks to anyone who could give me some clues on how to proceed.
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Hi Dadioh
Yesterday was the first day i see your advices and your name on the internet.
Yesterday and today i could fix:
1. Macbook pro 15 no light.
2. Macbook pro 17 no light.
3. Macbook 13 no light.
4. Macbook pro 17 no wireless.
I really thank you and appritiate your help.
Thanks
P.S. I have a macbook pro 13 which spilled liquid on it, I cleaned it and it started but when i connect the charger it is only green.
I think it is not charging, can you help me with this?
It is Macbook Pro 13", A1278, 2009
Thanks
Yesterday was the first day i see your advices and your name on the internet.
Yesterday and today i could fix:
1. Macbook pro 15 no light.
2. Macbook pro 17 no light.
3. Macbook 13 no light.
4. Macbook pro 17 no wireless.
I really thank you and appritiate your help.
Thanks
P.S. I have a macbook pro 13 which spilled liquid on it, I cleaned it and it started but when i connect the charger it is only green.
I think it is not charging, can you help me with this?
It is Macbook Pro 13", A1278, 2009
Thanks
Given that you "know" the cause of the blown fuse is now removed then it is probably OK to temporarily short the fuse to see if it solves the problem. However, proceed at your own risk. If you want to be extra safe then measure impedance to ground on all the WLED driver pins and compare to the chart to ensure nothing else is failed. In particular measure the impedance from the 27V backlight pins to ground and make sure that it is not shorted.
Of course the "really" safe way would be to replace the fuse and then, if there is still something wrong it just blows again. If it works then you are good to go.
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Well you would need to document exactly what the issue is with each case and post here. Include a description of what the background history of the board is (liquid, damage, etc...) and what you have tried so far. Any pictures would be helpful.
The idea of the thread is for us all to help each other out. I do my best to help but I have a very busy schedule so I can't make any promises. But there are a lot of other knowledgeable and helpful people on this thread that can all chip in.
For the non-charging Macbook there may be more relevant information in my other troubleshooting thread linked below.
https://forums.macrumors.com/threads/1122338/
All the four which i listed was fixed, That was liquid on them, the 3 which had problem with back light, i fixed buy replaceing of fuse ( after i saw your advices about how it seems out.
and the one had problem with Wireless, the problem was a smd close to the air port connector,i think it is a choke, which i replaced.
Thanks too much.
How can i get the schematices for macbookes?
and the one had problem with Wireless, the problem was a smd close to the air port connector,i think it is a choke, which i replaced.
Thanks too much.
How can i get the schematices for macbookes?
OK. I misunderstood. You actually fixed the first 4. That is great news. Congratulations.
You just need to enable Private Messages (PM) if possible and I can send you a link.
You mean MB466? The Macbook aluminum unibody from 2008? If so, I believe there are pictures earlier in the thread indicating where to measure. It is the same pinout on the LVDS connector as the MBP13 model as well.
Hi Dadioh
yesterday i fixed a macbook pro that had no back light, by shorting the fuse,and i teated it about two hour with a spare LCD and LVDS cable.
But just when i connected back the orginal cable and lcd the logic board smoked up.
To repair it i replaced the
lcd connector
shorted the fuse
replaced the driver 8543 ( taken of a mac which got water too and not starting )
replaced the diode
replaced the transistor R33F
Replaced the white capacitator for the lcd
What can i do more?
yesterday i fixed a macbook pro that had no back light, by shorting the fuse,and i teated it about two hour with a spare LCD and LVDS cable.
But just when i connected back the orginal cable and lcd the logic board smoked up.
To repair it i replaced the
lcd connector
shorted the fuse
replaced the driver 8543 ( taken of a mac which got water too and not starting )
replaced the diode
replaced the transistor R33F
Replaced the white capacitator for the lcd
What can i do more?
Attachments
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Hi all,
at first, thank you for all of your great work.
This thread is awesome and brought my panic down after I've changed a broken LCD from my "new" macbook pro 15" mid 2010 and still have no backlite.
I've read the whole thread but I couldn't find a picture of a Mid 2010 i5 board with a marked fuse.
I've made pictures of both side and I think I've fond the fuse but I'm realy not shure. The fuse looks damaged and some kind of coating is arround the fuse.
I've linked the pictures due to theire size (5184 x 3456).
http://imageshack.us/photo/my-images/685/macbookmid20102.jpg/
http://imageshack.us/photo/my-images/10/macbookmid20101.jpg/
It would be nice if someone of you could please have a look and give me some help to find the fuse.
Many thanks in advance for your help.
Regards from Germany,
Sebastian
at first, thank you for all of your great work.
This thread is awesome and brought my panic down after I've changed a broken LCD from my "new" macbook pro 15" mid 2010 and still have no backlite.
I've read the whole thread but I couldn't find a picture of a Mid 2010 i5 board with a marked fuse.
I've made pictures of both side and I think I've fond the fuse but I'm realy not shure. The fuse looks damaged and some kind of coating is arround the fuse.
I've linked the pictures due to theire size (5184 x 3456).
http://imageshack.us/photo/my-images/685/macbookmid20102.jpg/
http://imageshack.us/photo/my-images/10/macbookmid20101.jpg/
It would be nice if someone of you could please have a look and give me some help to find the fuse.
Many thanks in advance for your help.
Regards from Germany,
Sebastian
Can you post a picture of the damaged traces on the logic board. There is always hope
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Dadioh, sorry for the delay. Been preoccupied. Here is a pic of the connector with some missing traces. Any suggestions would be greatly appreciated. Thank you again for your assistance.
Attachments
![IMG_1534[1].jpg](/data/attachments/281/281016-9e46df7361eed8a95637f1a1e520352a.jpg)
Hi to all,
I damaged my macbook 13 early 2011 i7 with water, everything is still working, except the backlight. Does anybody knows if there is fuse to change?
Regards
Hi fozzifoz
If you see close to the LCD connector there is a little yellow device which have a Letter P on it, That must be the fuse for you MCP.