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Discussion Starter · #1 ·
Hello all. I recently acquired a 13 inch MBP. I believe it is a 2009 model. (Purchased from Ebay)

All I get from this computer is a very dim green light on the magsafe connector.

I have tried a new DC in board and a new Magsafe PS. I have also tried an SMC reset, with no luck. I have taken the logic board out and examined it finding no obvious damage. I cleaned the board and even with everything disconnected I still only get a dim green light.

If I plug my Magsafe into a functioning laptop, then immediately switch to the problem MB, I can sometimes get a bright green light, but after a minute or so, the green light fades.

From what I can tell by reading online, I believe the fuse for the screen is open. But I wouldn't think that would kill the entire LB.

I have tried the keyboard bypass to try and start it up with no luck, but I do get power to that area.

If any one has an idea of where else I could look at that would fantastic. I am comfortable with doing my own repairs, even soldering if necessary, I'm just unsure where to look. Thanks
 

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It seems you got a liquid damaged logic board. You should read this MacRumors thread:

SMC Issue on MBP 13 - Hardware Troubleshooting Guide - MacRumors Forums

The board must be cleaned before testing it. I immerse the board in a tub with warm water and dishwashing liquid for 30 minutes then rub the board components with a toothbrush when the board is still in the warm water. If the spilled liquid as sugar in it the warm water will dissolve it. Then I spray demineralized water on the board to rince it and compressed air (or hot air gun) to dry it. Don't take chance and let the board dry 24 hrs before testing it.

Many people use isopropyl alcohol 99% to clean their board but it's not so good if the spilled liquid has sugar in it.

When the board is ready for testing, only connect the fan and the magsafe board and check if you have 3.42v on one of the two jumper pads (second pad is 0v). The green light on the magsafe tip light must be strong and steady. If the green light is ok and you got the 3.42v then try to jump the power pads and the fan should run if the G3hot line is OK.

You'll find all the hints in the Macrumors thread. Good luck.
 

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PS: the board should work even if the backlight fuse is blown. If so, you'll get no screen lightning but you should have video onscreen. Carefully check the LVDS socket and connector for black spots or desoldered legs on the socket. On this MBP model there's no separate inverter board. The inverter assy is soldered to the logic board and the power to lighten the screen goes thru the LVDS socket to the screen.
 

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Discussion Starter · #4 ·
Ok, sounds good. Thank you very much for the advice. I work this weekend, but I will try this when I get a chance.
 

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Discussion Starter · #5 ·
Wow its been a long time. I still haven't fixed it but I believe I have found the problem. Close to the bottom of the board, there is a small hole, and the circuits within the board actually run through the hole, making a connection to circuits on the opposite side. I'm unsure how the circuit was damaged, but I believe if I'm able to complete the connection, it should fix the problem.
 
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