In case you are new to Macbook laptops, you might have noticed your laptop Wi-Fi is on when it comes out of sleep mode. And since it is running all the time, you feel that your battery life is shorter. There is nothing to find when you go into system preferences. So how do you turn off wireless LAN in sleep mode?
Well, there is nothing to worry about here as it is off in sleep mode. It shall be noted that Wi-Fi will stay connected only if you have plugged it in. So unplug it when you are sleeping or not using it to ensure that Wi-Fi is disconnected in sleep mode.
If the Macbook is not connected to charger and when you lift its lid, then you will find Wi-Fi radio on it will search for a moment or two and then connect. Keep in mind we are assuming that there is nothing in background that is keeping the laptop awake – preventing it to go into sleep mode properly.