how to turn on macbook pro without power button

Remove memory, graphics card and CPU and reinstall, checking for any bent pins on the CPU and CPU socket. Components not installed or seated properly.If your board has an extra 12v socket near the CPU, ensure the correct lead from the power supply is attached in addition to the large 24-pin ATX connector. Power leads improperly attached to motherboard.If you can see the coloured wires inside the black outer protection, it could be time to buy a new power supply unit (PSU).

Weak points are at the ends where it joins the black brick and at the plug which connects to the laptop. If you have a spare power cable that will plug into your power supply, this is a much quicker way to test that it isn’t the fuse at fault.Ĭheck over the wire itself, as power supplies get beaten up, especially if you carry them everywhere. Use a screwdriver to remove the fuse and swap it for one that’s known to be good. If it’s the correct charger, next check the fuse in the plug.

Many laptops – especially from the same manufacturer – use the same size plug, and if you own more than one, it’s not too difficult to plug in the wrong power supply, which might provide a different voltage or not enough current. Older devices in particular can lose significant amounts of battery when in sleep mode, and may therefore not turn on if one of these chargers are used. Some third-party chargers also output power at a speed that is only equivalent to what your device requires to run. Stickers or markings on both the power supply and laptop should confirm this. So check that the adapter is indeed the correct one for your laptop and is delivering the right voltage and amps.

How to turn on macbook pro without power button