Apple Self Repair Guides

Warning Resetting the power manager will permanently remove a RAM disk if present and all of its contents You will also need to reset the date and time using the Date Time system preference pane

6. Press Caps Lock key to see if key light comes on. If it does, hold power button down for six seconds to shut down the computer and restart.

1. If it still doesn't start, verify power button cable is connected properly to top case flex cable assembly and that the flex cable is connected correctly to the logic board, if power button is not functioning correctly or damaged, replace the top case.
2. Disconnect keyboard completely. Inspect connectors. Restart with keyboard disconnected.
3. Remove any additional RAM.
4. Remove AirPort Extreme Card.
5. Verify Sound/DC-in board cable is securely connected.
6. Try disconnecting the AirPort Extreme flex connector from the logic board and start the computer. If it starts, shut it down and check the flex cable connector and the connector on the logic board and replace the damaged parts.
7. Repeat step 12 with the following flex cables one at a time, reconnecting each before proceeding to the next cable:

• Sound/DC-in flex cable
• Hard drive flex cable
• Optical drive flex cable
• PC card cage flex cable
• Keyboard flex cable
• Trackpad flex cable
• Right USB flex cable
• Modem flex cable

If the computer starts up, inspect the flex cable connector and its connector on the logic board for damage and replace the damaged parts.

1. Try known-good Sound/DC-in board.
2. Replace logic board.