Try using a multimeter to test the output of the AC adapter. There may be a reset button or hole on the back. Do you get anything, noise, or lights?
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Try using a multimeter to test the output of the AC adapter. Ty resetting the power manager again with the battery removed and power adapter disconnected. Press/hold the reset button between the ADB and serial ports for 30 seconds, then connect just the power adapter and start up. Do you get anything, noise, or lights?
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Reset the PMU, heres how: http://support.apple.com/kb/HT1781?viewlocale=en_US