Touch screen is not responding - Solutions - Huaqiang Electronic Network

[Fault Phenomenon]: The touch screen is unresponsive and does not react to any touch input.
[Fault Analysis and Resolution]: Begin by checking the connection cables for any looseness or damage. Then, verify if there's a conflict between the serial port and interrupt settings. If a conflict exists, adjust the system resources accordingly. Next, inspect the touch screen surface for cracks or scratches. If found, replace the screen immediately. Also, check for dirt or debris on the screen surface and clean it with a soft cloth. Observe the control box indicator light—normally, it should be green and blinking.
If all previous steps are normal, use the replacement method: first replace the control box, then the touch screen, and finally the host computer.

1) The issue might be due to a faulty connection. Ensure that the touch screen is properly connected to the host’s keyboard port (which provides the 5V operating voltage). Check all connections thoroughly.

2) It could be an incorrect serial port selection during driver installation. The selected port may not match the one actually used. Uninstall the current driver and reinstall it, making sure the correct serial port is chosen.

3) If the host is a custom-built unit with an OEM operating system, it might have been modified by the manufacturer, causing non-standard serial communication. This can lead to incompatibility with the touch screen driver. In such cases, consider formatting the hard drive and reinstalling the OS before installing the touch screen driver.

4) An outdated driver version could also cause issues. Install the latest driver available from the manufacturer’s website.

5) Conflicts with other hardware devices using the same serial port resources might be the cause. Check each device and adjust their settings if necessary. For example, some network cards default to IRQ 3, which may conflict with COM2. Change the network card’s IRQ to an unused one.

For resistive touch screens, follow these repair steps:
1) Verify that the touch screen is correctly connected. One of the connections should come from the host’s keyboard port (providing 5V power). Check all connections again.
2) Check the control box’s indicator light. If it is off or red, the control box may be faulty and needs replacement.
3) If the above checks are clear, try removing the driver and restarting the computer to reinstall it. Alternatively, use a newer driver version.
4) Check for conflicts with other hardware devices using the serial port. Adjust their settings as needed. For instance, some network cards may use IRQ 3, conflicting with COM2. Change the network card’s IRQ to an unused one.
5) If the touch screen has been in use for several years (3–4 years), some areas may become unresponsive due to wear. In this case, replacing the touch screen is recommended.

For capacitive touch screens, here are the troubleshooting steps:
1) Ensure the touch screen is properly connected. If using an external control box, connect the cable from the screen through the return slot to the control box. Power should be supplied via a keyboard conversion head. Make sure to remove the small rubber head next to the RS232 port before connecting. Connect one end to the host’s keyboard port and the other to the computer’s keyboard. Insert the 5V power supply into the RS232 port. Connect the RS232 connector of the control box to the host’s 9-pin port. If your host uses a 25-pin port, purchase a 9-to-25 adapter. If the host’s keyboard port is original, consider buying a large keyboard-to-keypad adapter.
2) For built-in control cards, check the jumper settings on the control card. Since different systems may use different peripherals, the jumper settings help avoid conflicts. Micro Touch provides jumper descriptions so users can configure the COM port settings appropriately.

COM Port	I/O Address	A1	A2	A3	A4	A5	A6
COM1	3F8-3FF	ON	OFF	ON	OFF	ON	OFF
COM2	2F8-2FF	OFF	ON	ON	OFF	ON	OFF
COM3	3E8-3EF	ON	OFF	OFF	ON	ON	OFF
COM4	2E8-2EF	OFF	ON	OFF	ON	ON	OFF
COM5	2E0-3E8	OFF	ON	OFF	ON	OFF	ON
COM6	2F0-2F8	OFF	ON	ON	OFF	OFF	ON
COM7	3E0-3E8	ON	OFF	OFF	ON	OFF	ON
COM8	3F0-3F8	ON	OFF	ON	OFF	OFF	ON

The COM port and interrupt jumper settings should be configured accordingly. Special cases may require individual attention.
COM1 → IRQ4 | COM2 → IRQ3 | COM3 → IRQ4 | COM4 → IRQ3