Dead Motor? Or so I thought...

A few months ago, I put the finishing touches on my Prusa i3 rework. As proud as I was, I got quite wrapped up in work and I unfortunately couldn't use it that much. This week, however, I decided to look at it and use it again. I was about to print a new case for my phone, got it all heated up, and started to print. I came back 2 hours later to find out that nothing had actually printed, despite saying "Finished. 2 hours 7 minutes" I tried to start it again, and I saw that the motor was not working.

I went into some trial and error: I connected the wire from my y Axis to my extruder motor to test the motor. Motor is good.
I swapped around the stepsticks to ensure that it wasn't the stepsticks. Stepsticks are Good.

Then I realized something. Whenever I tried to move the motor, a yellow light beneath the RAMPS board on the atmega 2560 would light up. I tried it with the other motors, and it didn't light up. By the way, I'm using a full graphic smart controller.

Does anyone have any insight on to why this is happening?

not sure if the light up got to do with it, when mine is switched off and unplugged, and if I move any motor fast enough, even my endstop lights up, but my printer works perfect

It's not my endstop light, it's a light on the board of the atmega.

I use a full graphic smart controller and im pretty sure it not the issue here, how-ever that little light you are talking about should be green, perhaps you should go back to making sure the power supply is properly tuned to the 12v output using the tinny adjustment nob on it , and then retighten all the connections, and try to re flash marlin making sure u clear the board first by using the eeprom_clear sketch.

it can also be as simple as not enough power going to the steppers once belts are all in place, Did you try increasing it with the little potentiometer?

I reflashed it, still didn't make a difference. I also moved around the pontentiometer.