Check the led light situation. Eg. KCA-U001L-R3C , after connect power led light keep short bright (around 2s),then light out .It means controller already finishes self-check . When people touch panel ,the light will flash as touch frequency ; without connect power ,the led light keep long bright .Above information indicates controller works well .Refer to LED indicator situation.
（1）Check if controller connects ground
（2）Check if panel connects well with controller
（3）Check if any much interference: Move touch panel away from LCD monitor , touch panel
works well ? If controller works well ,touch is ok , It should be LCD monitor interference problem.
Check if driver installed successfully , if yes , then calibrate . After calibration it will work properly.
（1）Check the led light status on controller whether is normal. When touch panel , the led flash is same frequency as touch ?
（2）Change controller or test again in another PC.
（3）Change cables to test if connect well
（4）Check USB interface whether is ok
（5）Check the touch function is enable or disable. If disable ,please choose enable it .
(1) Check if other’s company driver installed? Please uninstall firstly ,then install keetouch driver.
(2) Check if COM interface was used by other devices
(3) Please the driver version Whether is match the OS.
(1) Check if COM interface is used by others.
(2) USB series --- Check if driver installed successfully , open UPDD driver console, check on the left top “Keetouch ,KCA USB Series” is red font or not .If it’s red, means drivers installed abnormally or USB interface has problem. Re-install driver or change USB interface .
Open the driver setting or double click driver icon on right bottom task bar.Choose Calibration item, revise margin value from 5 to 1.Or change to smaller values according to your truth application.