Common HMI LCD Touch Screnn Failures and Solutions

If you are an inexperienced GUI engineer, you will feel helpless if the HMI touch screen breaks.It may also slow down the process.Therefore, it is important to understand the cause and solution of the HMI touch screen problem.With these solutions, you can solve your problems by yourself.

Common failures of HMI touch screens are:

1 fault.The touch screen is inconsistent

The position of the finger does not match the cursor.

Reason: after installing the driver, when the position is calibrated, an unstable contact point.

Solution: recalibrate the center.

Failure 2: some touch areas have inconsistent responses

Cause: the touch screen surface accumulated thick dust or scale, affecting signal transmission.

Solution: clean the touch screen.In particular, the sound reflection stripes on the edge of the touch screen.When cleaning the screen, please remember to cut off the power to avoid damage.


Fault 3: no response from touch screen

There are many reasons for this, please check the following:

The touch screen surface accumulated thick dust or scale, affect the signal transmission.

Touch screen fault;

Touch screen control card fault;

(4) touch screen signal line fault;

(5) computer host serial port fault;

6. Computer operating system fault;

Touch screen driver installation error.


1.Check how the touch screen’s signal LED is flashing.Under normal circumstances, the light flashes periodically, usually once per second.When touching the screen, the light will remain on, release the finger, the light will resume flashing.
2. If the signal LED indicator is on all the time without any touch, please check whether you need to clean the screen.Then check that the serial port of the hardware connection is the same as the serial port you selected in the software.Next, check whether the serial port of the computer host works normally.
3. After installing the driver for the first calibration, please note system errors, such as “control card not found”, “touch screen not connected”.Please check the corresponding parts according to the error message.For example, check that the touch screen signal line is firmly connected to the control card and that all keyboard cables are connected to the host.
4. If you still cannot solve the problem, please seek professional help.