So at the begining of Night 3, you'll get some Casual Bongos, you'll go to the hub normally, you'll check on Ballora, see how messed up she is, check on Foxy, see her/his shadow and then you'll be told not to check on Baby and go to the Parts Department. ( I cant remember the actual name)

You can head to Baby's and go into the Crawl space for some Exposition and Back Story (neat little easter egg) or you can go to Foxy's walkway. Doing so you'll be given a Flash Beacon, which will give you a small 0.5 flash of light to discern your location to the door and if Foxy's looking at you. The overhead speaker says to use it sparingly but, use it as much as you need to. He's not very trustworthy.

Now, we're in the Parts Department, and immediately you'll be face to face with Funtime Freddy, who is shut down. To make sure he doesnt come back online while other people work on him you need to take his power core. This part is simple. Click the button near the Right Cheek, then the Left Cheek, then The Right Eye and lastly the Upper Mouth. His face will then burst open and under his jaw will be another button. Pressing it will open his chest and allow you to take his power core.

Then you need to get Bonnie's, who has his own power source and can move around. Of course, he makes things difficult. He'll move from Freddy's Shoulders and Right Leg. Not in order, but based on where your cursor is. Now this is the hard part. To get Bonnie, you need to press the button under his Bowtie, its big and black. Hard to miss. But as soon as your cursor is too close, he'll book it. What you need to do is bait him into raising to a point where you can hit the button and quickly doing so. But Bonnie may not be spawning fast enough for you to do this, and you probably got frustrated at it and came here to see how. Well the easiest way to get him to spawn, is to put your cursor around Freddy's mic hand then quickly transitioning to Freddy's Face. If done right, Bonnie will be in plain sight and you just have to wait. You may not get him your first few tries, but keep it going and eventually you'll bag him.

Well, my best guess is that SCOTT CAWTHON didnt program this part correctly and instead it popped out like this, in where your cursor has to be the furthest point away from one of his spawns instead of a set distance away from them. This would mean that you have to put your cursor to any of the other corners to get Bonnie to spawn there. Although this could be intentional, and if so SCOTT YOU S.O.B.