There are a few issues that might cause a MacBook to not boot up like you're experiencing, such as a damaged power button on the top case (usually due to spill damage), a bad logic board, or other various small issues. Does the MagSafe light illuminate when plugged into the DC-in board? Is the battery receiving power (the level indicator should light up when the button is pressed)? Have you tried resetting the PMU/SMC by holding down the power button for 10 seconds while the machine is connected to AC power? You should see the sleep light flicker and hear a tone. If that doesn't work, you might want to try [http://support.apple.com/kb/ht1379|resetting the PRAM]. Hope this helps!
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There are a few issues that might cause a MacBook to not boot up like you're experiencing, such as a damaged power button on the top case (sometimes due to spill damage), a bad logic board, or other various small issues. Does the MagSafe light illuminate when plugged into the DC-in board? Is the battery receiving power (the level indicator should light up when the button is pressed)? Have you tried resetting the PMU/SMC by holding down the power button for 10 seconds while the machine is connected to AC power? You should see the sleep light flicker and hear a tone. If that doesn't work, you might want to try [http://support.apple.com/kb/ht1379|resetting the PRAM]. Hope this helps!
There are a few issues that might cause a MacBook to not boot up like you're experiencing, such as a damaged power button on the top case (usually due to spill damage), a bad logic board, or other various small issues. Does the MagSafe light illuminate when plugged into the DC-in board? Is the battery receiving power (the level indicator should light up when the button is pressed)? Have you tried resetting the PMU/SMC by holding down the power button for 10 seconds while the machine is connected to AC power? You should see the sleep light flicker and hear a tone. If that doesn't work, you might want to try [http://support.apple.com/kb/ht1379|resetting the PRAM]. Hope this helps!