I have recently acquired a 3DS from a friend who had good intentions of giving it to me however, the 3D slider is broken and therefore I cannot set the screen to 3D. I am perfectly fine with this because you can still play the games without 3D but, the 3DS will not allow me to play games because he reset the device and I cannot pass the 3D screen check. I was hoping there was a solution to this because it is a waste of a 3DS just because I cannot pass this test.
Unfortunately, but there doesn't appear to be a way to bypass this, and you do need to enable the 3D effect by pressing the 3D slider all the way to the top to start the 3D Screen Check process, so that does kinda mean you or your friend will have to have this 3DS repaired if you wish to use it, sorry.
So you or your friend give a call to Nintendo's 1-800-255-3700 (6 am ~ 7 pm Pacific, everyday) Customer Service number, and they can set up the repair process.