Why is my touch screen not working properly?

"Okay this could be down to a few things, connection issues or the flex could be damaged.

First please try a hard reset by holding down the power and home button at the same time until the screen goes black and the apple logo appears, then let go. if the issue is still present please do the following.

Complete the following guide and remove your display completely iPhone 4 (GSM/AT&T) Screen Replacement

Once you have done this check the following locations for any type of damage,

Both sides of flex, as there is a snag point with could have been damaged.

These connectors are for both the LCD and the touch screen, it is worth checking both and possible cleaning them with isopropyl alcohol and a cotton bud if they appear dirty in some way.

It is likely the flex has become damaged, if it has please replace and the issue should be resolved. If the flex appears okay, sadly you may have to resort to replacing the screen anyway.

Please let me know how you get on and I'm alway here to help just ask.

Best Regards

Brendan Mills"

"First try a hard reset

Press and hole the power and home button togeather for about 7 seconds then let go of home and keep pressing power this will restart it and see if the touch work then"

As we know to replace iphone 4/4s power button we unsrew it all the way until we raech power flex at the same time during replacement of power button you might left touch flex losen or it get broken try with new screen if it works then fine otherwise try replacing another power flex it might be problem with flex who actually making touch not to respond properly thanks