Power Issues, Power Adapter Dead, No Power
1 Check for damaged pins or magnetic debris on the MagSafe power
adapter. If the pins are okay, reseat the power adapter connector and
make sure it is fully inserted.
NOTE Refer to Knowledge Base documents 303566,“MacBook Pro:
Troubleshooting MagSafe power adapters with stuck pins,” and 302461,
“Troubleshooting iBook, PowerBook G4, and MacBook Pro power
adapters.”
2 Remove any connected peripherals.
3 Try a known-good power outlet.
4 Remove the battery and AC power.
5 Press the Caps Lock key to see if the light on the key comes on. If it does,
hold the power button down for 6 seconds to shut down the computer
and restart.
6 Reset parameter random-access memory (PRAM) by pressing the power
button, then holding down the Option-Command-P-R keys until you
hear the startup chime at least one additional time after the initial startup
chime.
7 Reset the Power Manager.
NOTE Refer to Knowledge Base document 303319, “Resetting MacBook
and MacBook Pro System Management Controller (SMC).”
WARNING Make sure you do not hold down the Fn key when resetting
the Power Manager. Resetting the Power Manager means you will also need
to reset the date and time in Date & Time preferences.
8 Test each RAM slot individually with known-good RAM. The computer
should still start with only one known-good dual inline memory module
(DIMM).
9 Remove the AirPort Extreme Card.
10 If the computer starts on battery power only, try replacing the MagSafe
board with a known-good MagSafe DC-in board.
11 Verify cable connections and check cables for damage
12 Verify that the power button is connected properly to the logic board. If
the power button is not functioning correctly or damaged, replace the
top case.
13 Replace the logic board.