Why isn't my phone screen working? What cables control the screen?

I replaced my broken phone screen the way that i should, I'm positive. The phone still turns on/off, and rings when called or texted, but THE TOUCH REMAINS UNRESPONSIVE and THE SCREEN ONLY LIGHTS UP DARK GREY/BLACK. If anyone knows what cables contol the actual color in the screen and the touch, please let me know. The phone DOES turn on and light up! It just doesn't have color and has unresponsive touch! Please help ASAP!