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MacBook Pro 15" Core 2 Duo 2.4 GHz Model A1226 I replaced the display and the logic board of my MacBook Pro. Both were functioning fine before. After the reassembly the MacBook was working fine as well. So I took it with me to work with it but from now I wasn’t able to start it again. So I disassambled it again to the point of disconnecting all cables from the logic board. After that I reassembled the MacBook step by step. Before putting back the upper case I tried to boot the MacBook by connecting the two small power pads on the logic board and it worked. So I reconnected the trackpad and keyboard ribbon cable with the logic board and pushed the power button: Still the MacBook worked. Finally I reassembled the rest and pushed the power button again. This time the MacBook failed to start as before. I get a light on the Magsafe adapter and can hear the HDD rotating but the fans don’t work and the screen stays black. I also did a SMC reset but the MacBook doesn’t boot either. Does anybody have any further ideas how to fix this problem?
I would suspect that you are shorting out due to the wrong placement of a screw. Try taking out all the case screws and give it a try. You may have to go back through the guide and measure each screw to make sure they are placed correctly.
