Are you getting voltage at the lvds connector? How does the connector look? Check with a loupe on the pins inside, once upon a time mine were all bent out of whack, had to straighten them.
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MacBook Pro Unibody - No Backlight - Logic Board Question
- Thread starter Dadioh
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Are you getting voltage at the lvds connector? How does the connector look? Check with a loupe on the pins inside, once upon a time mine were all bent out of whack, had to straighten them.
Checked again and getting 20.5v at the connector and the connector does look good. Do you know what the voltage should be on PPVOUT_SW_LCDBKLT?
what are those things in the picture with "22 1e88" and a plus sign written on them?
Diodes most likely, and from what my board looks like (A1286 late 2008) not part of the backlight circuit.
The file I have suggests mid-2010 MBP15 A1286 is 820-2330 M98. Was there more than one model of 15" MBP in 2010?
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Anyone come across the boardview files for the MacBook Air 13" 2010/2011 A1369 and the 2012/2013 A1466 machines yet?
Macbook Pro 15" 2009 2.53ghz core 2 duo
Hi,
Would be glad if someone can throw some suggestions if they have come across the same type of problem in the past. I have been working on this Macbook pro 15" mid 2009 2.53 core 2 duo machine. It does start up all ok but when booting OSX it shows apple icon, folder question mark and circle with line across all at the same time and it keeps on changing. It eventually does boot up to Lion (Mountain Lion also tried but all the same) but takes say 5-6 minutes to boot instead of 1 minute normal boot time. Then it will kernel panic at some point and also will work very very slow in the OSX. You can click the safari browser and wait for like 30-40seconds to open which is not normal on freshly installed hard drive. I have tried resetting the PRAM, SMC bypass does the same, replaced HDD Cable from working machine, replaced rams 4gb modules, 2gb modules, replaced hard drives 5400rpm, 7200rpm but nothing seems to work..
Any help would be highly appreciated.
Thanks.
Hi,
Would be glad if someone can throw some suggestions if they have come across the same type of problem in the past. I have been working on this Macbook pro 15" mid 2009 2.53 core 2 duo machine. It does start up all ok but when booting OSX it shows apple icon, folder question mark and circle with line across all at the same time and it keeps on changing. It eventually does boot up to Lion (Mountain Lion also tried but all the same) but takes say 5-6 minutes to boot instead of 1 minute normal boot time. Then it will kernel panic at some point and also will work very very slow in the OSX. You can click the safari browser and wait for like 30-40seconds to open which is not normal on freshly installed hard drive. I have tried resetting the PRAM, SMC bypass does the same, replaced HDD Cable from working machine, replaced rams 4gb modules, 2gb modules, replaced hard drives 5400rpm, 7200rpm but nothing seems to work..
Any help would be highly appreciated.
Thanks.
Never seen this sort of behavior before with the boot icon changing between the 3 states
As far as slow operation and the kernel panic I have seen this behavior when there is something wrong with one of the sensors and the SMC seems to be sending constant interrupts to the CPU. You would see "kernel task" (or something like that) chewing up all of the CPU time.
There is a utility around called MRI (Mac Resource Inspector) that can be placed on a bootable USB stick and then check all of your hardware and sensors. It might give you a clue as to what is wrong.
Never seen this sort of behavior before with the boot icon changing between the 3 states
As far as slow operation and the kernel panic I have seen this behavior when there is something wrong with one of the sensors and the SMC seems to be sending constant interrupts to the CPU. You would see "kernel task" (or something like that) chewing up all of the CPU time.
There is a utility around called MRI (Mac Resource Inspector) that can be placed on a bootable USB stick and then check all of your hardware and sensors. It might give you a clue as to what is wrong.
NOTE: Never mind. I missed the sentence about the originator have tried new HD with I presume have new and clean OSX installed.
To me this sounded like an OSX confusion problem, and not hardware. OSX LION and OSX MOUNTAIN LION have big change in them that may cause your problem if your OS file system is corrupted, i.e., you may have a mix and matched "kext" aka kernel extension. ML have abandoned support for 32-bit device supports (the reason ML can only be installed in later model MB/MBPs and I think 2008/2009 models are at that threshold. I suggest that you get a test HD loaded with clean OSX Lion and boot from that.
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Excellent point. I am a hardware guy so I tend to assume HW issues
As they say... When your only tool is a hammer, everything looks like a nail.
Thanks cmdrdata for your suggestion. But I have tried Lion and ML on two different hard drives 500gb but still the same. Another thing I must say that if I put Samsung 500gb 5400rpm (Brand New) it will take some 3 hours to get installed but if I use hitachi 500gb 5400rpm (again brand new) then installation takes mere 50 minutes. Even I cant believe this!!! I have never ever encountered such a problem before. Tried another working hard drive from another full working machine which has got lion on it and still the same. When booting it will show all 3 icons at the same time and boot up. Not a software issue for sure its hardware. Verbose mode will show several errors but it goes past quickly and the system still boots up and then takes ages to open any application when in OS. When you try this hard drive on another working machine it works a charm.
Help..
Thanks.
Never seen this sort of behavior before with the boot icon changing between the 3 states
As far as slow operation and the kernel panic I have seen this behavior when there is something wrong with one of the sensors and the SMC seems to be sending constant interrupts to the CPU. You would see "kernel task" (or something like that) chewing up all of the CPU time.
There is a utility around called MRI (Mac Resource Inspector) that can be placed on a bootable USB stick and then check all of your hardware and sensors. It might give you a clue as to what is wrong.
Hi Dadioh, thanks for your suggestion. I have this (3 icons at the same time when booting) issue with another A1278 13" 2009 2.26ghz core 2 duo machine as well. I haven't had a chance yet to dig in that but this 15" 2009 2.53 was important. Is this Mac Resource Inspector the same as AHT Apple Service Toolkit ? Hopefully I can find it.
Thanks.
Never seen this sort of behavior before with the boot icon changing between the 3 states
As far as slow operation and the kernel panic I have seen this behavior when there is something wrong with one of the sensors and the SMC seems to be sending constant interrupts to the CPU. You would see "kernel task" (or something like that) chewing up all of the CPU time.
There is a utility around called MRI (Mac Resource Inspector) that can be placed on a bootable USB stick and then check all of your hardware and sensors. It might give you a clue as to what is wrong.
Just to show the kernel panic error I have attached the pic. Thanks.
PS: No kernel panics or changing of 3 icons at the same time when booted from external usb hard drive with Lion or ML on. It boots swiftly and works perfect through USB, problem only when hard drive internally connected. HDD cable replaced twice dint change anything. Hdd connector all ok.
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So it seems like it is SATA related. Do you happen to have one of those DVD Caddy adapters that would allow you to place the hard drive in the caddy and use the optical drive SATA connector? That might determine if it is just the HDD SATA port. Maybe the ODD (Optical drive) SATA port is OK?
Long shot
I have had a couple of units with messed up SATA interfaces. Unfortunately there is not much between the MCP (Northbridge) and the port (some caps and filter inductors). So those boards are pretty much toast because I can't change the MCP.
So it seems like it is SATA related. Do you happen to have one of those DVD Caddy adapters that would allow you to place the hard drive in the caddy and use the optical drive SATA connector? That might determine if it is just the HDD SATA port. Maybe the ODD (Optical drive) SATA port is OK?
Long shot
I have had a couple of units with messed up SATA interfaces. Unfortunately there is not much between the MCP (Northbridge) and the port (some caps and filter inductors). So those boards are pretty much toast because I can't change the MCP.
Yes I have already ordered that sata DVD caddy adapter will receive in a day or two. I will then update back with the results. And yes there is not much of components between the northbridge and connector on this board which is why this problem seems to be very uncertain to solve now other than replacing the northbridge.
Thanks.
No other fuse so it will likely be an issue with the WLED driver orthe circuitry around it. Or possibly the lvds connector/cable. To troubleshoot that you will need some electronics experience and a schematic. A microscope and fine leads for your multimeter are helpful too.
Sounds like a possibility. I have that same machine but it is my wife's so tearing it apart is an unpopular option
Take a metal object and run around the black border of the glass display. Where it "sticks" is where the sleep magnet is. Then figure out where that lands on the top case and that is where the sensor will be.
I found where the magnet is on the right bottom of the frame of the screen. opened up the case and followed where that connects. I unscrewed where the bottom covers mount to that spine in the case. there is black small piece that connects to the whole next to the drive with two screws there. underneath that there is a orange small cable that leads from the sensor sleep sensor to the motherboard. Here comes the stupid move on my part. The cable was twisted so I was putting the gold leads down. GOLD LEADS TO THAT CABLE MUST BE FACING UP This whole time!!! If I hadn't taken that deal off I would have never found out that it was twisted underneath. Thanks guys and I will continue to surf on this thread to help others with problems
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So it seems like it is SATA related. Do you happen to have one of those DVD Caddy adapters that would allow you to place the hard drive in the caddy and use the optical drive SATA connector? That might determine if it is just the HDD SATA port. Maybe the ODD (Optical drive) SATA port is OK?
Long shot
I have had a couple of units with messed up SATA interfaces. Unfortunately there is not much between the MCP (Northbridge) and the port (some caps and filter inductors). So those boards are pretty much toast because I can't change the MCP.
UPDATE - Received this internal sata hdd caddy for optical drive space and it worked a charm. No problems at all. So basically that sata port is the problem. The macbook is now working minus the dvd drive but we can use that with external usb caddy. Thanks for your suggestion Dadioh.
Partial backlight fix
Dadioh/cmdrdata, et.al,
Needless to mention the great support by this forum, I am novice at soldering and electronics so any help is very much appreciated.
I received a Macbook Pro A1286 2009 with Backlight issue. The board had water damage. With your help, I was able to locate the backlight circuitry and determined that while the fuse was ok, there was some sort of short either in the FET, the 301K capacitor, or 0.1uf capacitor. So, I removed the 301K resistor, short didn't go away, but after removing the 0.1uf capacitor the short went away and the backlight came back. I was able to find replacement capacitors but with my rudimentary soldering skills I am unable to put the resistor and capacitor back on the board. I am wondering if it would be ok to leave them out?
Many thanks for your ideas.
Dadioh/cmdrdata, et.al,
Needless to mention the great support by this forum, I am novice at soldering and electronics so any help is very much appreciated.
I received a Macbook Pro A1286 2009 with Backlight issue. The board had water damage. With your help, I was able to locate the backlight circuitry and determined that while the fuse was ok, there was some sort of short either in the FET, the 301K capacitor, or 0.1uf capacitor. So, I removed the 301K resistor, short didn't go away, but after removing the 0.1uf capacitor the short went away and the backlight came back. I was able to find replacement capacitors but with my rudimentary soldering skills I am unable to put the resistor and capacitor back on the board. I am wondering if it would be ok to leave them out?
Many thanks for your ideas.
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R9808 and R9809 work as a voltage divider. When the backlight is enabled, pin 3 (drain) of Q9807 is pulled low. So the 12V from F9800 flows through R9808 and R9809 and should result in roughly 4V on pin 3 (gate) of Q9806. If the 301K resistor is missing then I am not sure what the gate on Q9806 would end up as. Depends on how much leakage current flows through Q9806 I guess. I would be concerned long term operating in this mode but given that you are unable to put it back I suppose that you could see how it goes. Worst case Q9806 could fail I suppose.
Less concerned about C9802 since I suspect it is just there to remove transients. If you ever see flickering of the backlight this might be the reason.
Commander Data may have more to share (or correct me
R9808 and R9809 work as a voltage divider. When the backlight is enabled, pin 3 (drain) of Q9807 is pulled low. So the 12V from F9800 flows through R9808 and R9809 and should result in roughly 4V on pin 3 (gate) of Q9806. If the 301K resistor is missing then I am not sure what the gate on Q9806 would end up as. Depends on how much leakage current flows through Q9806 I guess. I would be concerned long term operating in this mode but given that you are unable to put it back I suppose that you could see how it goes. Worst case Q9806 could fail I suppose.
Less concerned about C9802 since I suspect it is just there to remove transients. If you ever see flickering of the backlight this might be the reason.
Commander Data may have more to share (or correct me
Dadioh's analysis is correct. If you measure the voltages at the GATE/SOURCE/DRAIN of Q9806, what do you get? If you see 12v on all 3, then perhaps Q9806 is bad/shorted internally, allowing the 12vf to make it to the LED backlight circuitry and thus a working display. However, if this is not fixed, 12v source will continually be drawn and thus using power when it shouldn't. In general, power FETs in MBPs are used as a "controlled SWITCH", i.e., when the Gate is set to a few volts below Source, the S-D connection is made. Gate being equal to S or GND turned the switch off. Did you check C9802 off the board and verify it was shorted? If it was, that would be the reason the backlight being totally dark.
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Dadioh and cmdrdata,
Thanks for your reply, always very helpful.
C9802 was indeed short when I tested it. Q9806 didn't seem short between the drain pins and gate or source. I think I made an investigative error combined with my lack of soldering skills, I should have first remove the capacitor and tested, as Dadioh said that it may not matter as much, then resistor. I first removed the resistor and upon removal of capacitor I realized that it was the problem. Now I have to solder both difficult ones instead of just one
One question: Do you think it is possible/easier to solder the resistors/capacitors from a donor board then solder the new ones as the older ones are still tinned to certain extent?
Many Thanks!
Thanks for your reply, always very helpful.
C9802 was indeed short when I tested it. Q9806 didn't seem short between the drain pins and gate or source. I think I made an investigative error combined with my lack of soldering skills, I should have first remove the capacitor and tested, as Dadioh said that it may not matter as much, then resistor. I first removed the resistor and upon removal of capacitor I realized that it was the problem. Now I have to solder both difficult ones instead of just one
One question: Do you think it is possible/easier to solder the resistors/capacitors from a donor board then solder the new ones as the older ones are still tinned to certain extent?
Many Thanks!
Hi Guys ,
Any chance you guys can let me know where i can get hold of the this fuse?
Image[/QUOTE]
thanks
yaman,
You can buy many type of components, including these/similar Fuses at digikey.com or newark.com.
For fuses used in Mac backlights, you would need to know/use the following parameters when looking for fuse at sites above or at any location and you can generally find them in schematics:
1. Voltage (DC) - This would be either 32V or 24V depending on the Mac model.
2. Speed = Fast
3. Size: 0402 or 0603
4. Amperage: 3A or 2A
With regards to soldering, I have done removal with a hotair gun and soldered back using an iron. But I really wonder if it would be possible to just solder the new fuse next to the existing one (solder the newone on top or side of the older one) and and avoid removal as the existing one is dead anyway? But I don't know.
You can buy many type of components, including these/similar Fuses at digikey.com or newark.com.
For fuses used in Mac backlights, you would need to know/use the following parameters when looking for fuse at sites above or at any location and you can generally find them in schematics:
1. Voltage (DC) - This would be either 32V or 24V depending on the Mac model.
2. Speed = Fast
3. Size: 0402 or 0603
4. Amperage: 3A or 2A
With regards to soldering, I have done removal with a hotair gun and soldered back using an iron. But I really wonder if it would be possible to just solder the new fuse next to the existing one (solder the newone on top or side of the older one) and and avoid removal as the existing one is dead anyway? But I don't know.
I have a Mac book Pro early 2011 13 inch with no back light.
New to the board just signed up. I have read all 60 of these pages and have learned a lot.
I purchased two laptops on eBay, one with a broken screen and one was a bad motherboard and thought I can get a working laptop for cheap.
But the metal clip on the laptop on the screen cable was missing and I tried to tape the connector in place. I put it together and started it up and smelled smoke. A tiny resistor next to the LCDV was fried. I glued the cable in place and tried to see if it would work but nope.
Might have blown a fuse too. It’s the same board 820-2936-B as cetchmoh and r0k5t4r have the 13 inch, although they never reported getting theirs to work, cetchmoh has posted many pictures for me to look at.
{Edit}
From what I’ve read so far, the thing with the “P” on it in this 1st picture http://www.Timothean.com/fuse.bmp , is a fuse and it’s showing no continuity, which means it’s blown. Am I corrected this is the fuse?
Because I purchased a fuse from a guy on eBay that looks like the part that is actually burned up in these pictures. The .020 by .040 square in the lower right corner picture 2.
http://www.Timothean.com/2.BMP
And the capacitor below in picture 3?
http://www.Timothean.com/1o3.BMP
The resisters in picture two and three still show continuity, even though they are little fried. Perhaps the fuse blowing might have saved them and they might not need be replaced. Maybe I can get away with cleaning them up a little bit and adding a little more solder. They look like they would be L9004 and C9015. Is that correct?
It looks like the F9700 3A 32 volt fuse in picture 1, am I correct?
Better to check twice then fry the board twice. From cetchmoh's schematics and pictures. I’m starting to learn how to read schematics a little bit.
Can anyone tell me what resister/capacitor these are? I don’t know how to read schematics and I think I might be able to solder a little, but I don’t want to do too much unnecessary soldering.
It seems like the LED schematics that cetchmoh posted, does not match the board layout of our main boards. I can’t find L9004 and C9015 on that schematic diagram. The test link print out he posted does match our board 820-2936-B. Does anyone have a systematic for 820-2936-B?
New to the board just signed up. I have read all 60 of these pages and have learned a lot.
I purchased two laptops on eBay, one with a broken screen and one was a bad motherboard and thought I can get a working laptop for cheap.
But the metal clip on the laptop on the screen cable was missing and I tried to tape the connector in place. I put it together and started it up and smelled smoke. A tiny resistor next to the LCDV was fried. I glued the cable in place and tried to see if it would work but nope.
Might have blown a fuse too. It’s the same board 820-2936-B as cetchmoh and r0k5t4r have the 13 inch, although they never reported getting theirs to work, cetchmoh has posted many pictures for me to look at.
{Edit}
From what I’ve read so far, the thing with the “P” on it in this 1st picture http://www.Timothean.com/fuse.bmp , is a fuse and it’s showing no continuity, which means it’s blown. Am I corrected this is the fuse?
Because I purchased a fuse from a guy on eBay that looks like the part that is actually burned up in these pictures. The .020 by .040 square in the lower right corner picture 2.
http://www.Timothean.com/2.BMP
And the capacitor below in picture 3?
http://www.Timothean.com/1o3.BMP
The resisters in picture two and three still show continuity, even though they are little fried. Perhaps the fuse blowing might have saved them and they might not need be replaced. Maybe I can get away with cleaning them up a little bit and adding a little more solder. They look like they would be L9004 and C9015. Is that correct?
It looks like the F9700 3A 32 volt fuse in picture 1, am I correct?
Better to check twice then fry the board twice. From cetchmoh's schematics and pictures. I’m starting to learn how to read schematics a little bit.
Can anyone tell me what resister/capacitor these are? I don’t know how to read schematics and I think I might be able to solder a little, but I don’t want to do too much unnecessary soldering.
It seems like the LED schematics that cetchmoh posted, does not match the board layout of our main boards. I can’t find L9004 and C9015 on that schematic diagram. The test link print out he posted does match our board 820-2936-B. Does anyone have a systematic for 820-2936-B?
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