Backlight shorted inside display assembly - pls help confirm diagnosis
Texto:
I have a Macbook Pro with an 820-00850 motherboard. It's been dropped a few times and had some liquid spills in the past. Recently the screen went black, heard a sizzle-pop! and smelled freshly cooked IC wafting from the lower assembly. The motherboard seems to have suffered minimal damage. The only blown component is a 402 (1005) smd chip that is apparently a secondary fuse of some sort. It's not the main backlight fuse and doesn't appear in my boardview or schematic. It's also vaporized so I can't tell exactly what it was. Pictures below.
[image|3051134]
[image|3051135]
***''If anyone knows what this mystery fuse was I'd be thankful for the info!''***
Whatever it was it blew fast enough to protect the rest of the board. With the LVDS connector unplugged the machine boots and works with an external display. However:
* when the LVDS connector is plugged in PPVOUT_S0_LCDBKLT is a dead short to ground from the the test point just past the vaporized fuse.
* Unplugging the LVDS connector from the t-con board and LCDBKLT measured at the same test point as before is no longer shorted.
* Measuring from the display connector on the t-con board (J0200) again shows LCDBKLT (I don't have schematics for the t-con so I don't the proper alias at this point but it's still the LCD power line that is supposed to carry around 44V) shorted to ground.
* Removing the small backlight connector on the right of side of the t-con board (J0803) opens the LCDBKLT line on J0200 but VLED on J0803 is a dead short to ground.
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I'm not a Macbook expert but to me this implies that it is the LED string itself that is shorted to ground and not anything on the t-con board itself.
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I'm not a Macbook expert but to me this implies that it is the LED string itself that is shorted to ground and not anything on the t-con board.
Can someone with more experience with these things ***''either confirm this diagnosis or suggest where I may be overlooking something important?''***
I'm operating under the assumption that I need to find a replacement display assembly to fix this problem. I'd hate to spend the $'s to do that and then find out there may be something simpler that might be wrong.
Backlight shorted inside display assembly - pls help confirm diagnosis
Texto:
I have a Macbook Pro with an 820-00850 motherboard. It's been dropped a few times and had some liquid spills in the past. Recently the screen went black, heard a sizzle-pop! and smelled freshly cooked IC wafting from the lower assembly. The motherboard seems to have suffered minimal damage. The only blown component is a 402 (1005) smd chip that is apparently a secondary fuse of some sort. It's not the main backlight fuse and doesn't appear in my boardview or schematic. It's also vaporized so I can't tell exactly what it was. Pictures below.
[image|3051134]
[image|3051135]
***''If anyone knows what this mystery fuse was I'd be thankful for the info!''***
Whatever it was it blew fast enough to protect the rest of the board. With the LVDS connector unplugged the machine boots and works with an external display. However:
* when the LVDS connector is plugged in PPVOUT_S0_LCDBKLT is a dead short to ground from the the test point just past the vaporized fuse.
* Unplugging the LVDS connector from the t-con board and LCDBKLT measured at the same test point as before is no longer shorted.
* Measuring from the display connector on the t-con board (J0200) again shows LCDBKLT (I don't have schematics for the t-con so I don't the proper alias at this point but it's still the LCD power line that is supposed to carry around 44V) shorted to ground.
* Removing the small backlight connector on the right of side of the t-con board (J0803) opens the LCDBKLT line on J0200 but VLED on J0803 is a dead short to ground.
I'm not a Macbook expert but to me this implies that it is the LED string itself that is shorted to ground and not anything on the t-con board itself.
Can someone with more experience with these things ***''either confirm this diagnosis or suggest where I may be overlooking something important?''***
I'm operating under the assumption that I need to find a replacement display assembly to fix this problem. I'd hate to spend the $'s to do that and then find out there may be something simpler that might be wrong.
Thanks in advance for any help!