yellow button > 1993 > clear/stop button(the red one) 5x press and you’ll see menu’s. then press # button beside (number 0 button). get a pointed tool, press little circle appear on upper left portion of the screen using any pointed tool then press the other one below right portion of the screen and test some area of screen, if you press it should be markedr on the screen where you press it.
then press OK and exit, reboot the machine and test again.
press and hold HOME and SIMPLIFIED SCREEN for over 3 seconds, then press SIMPLIFIED SCREEN again
And to enter the mode to enable you to calibrate the screen, press SIMPLIFIED SCREEN 4 times, press SUSPEND SCREEN, then press SIMPLIFIED SCREEN 4 more times. Then test as suggested in method 1