Touchscreen on All-in-one not working

[Prophicy]

Like many other users I am having the same issue with my Touchscreen. It all of a sudden after an update stopped working. I have done the steps listed around the forum. A fix for this would be great considering it's just a software issue.

[Bill_To]

Hi

What update caused this? Was this a HP Firmware update?

Where did you get the update (HP Support Assistant or Windows Update)?

Does your PC POST and can you load Windows or is it completely cooked?

[Prophicy]

Honestly, I'm not sure, this is not my desktop. Everything else is fine, the Pen and touch says No pen or touch input is available for this display. And the HID-compliant touch screen is not present in the device manager. I do 100% know that it is a touch screen because I have used it. I tried installing the Touch screen Firmware for AIO Pavilion 27 but I get an error saying:

This touch panel IC firmware update is for ILITEK only.
Please ignore this firmware update program and exit this program.

[Bill_To]

Hi

Very confusing. I am guessing the touchscreen worked before the update, now it doesn't.

You have no Device Manager errors.

Maybe try installing the old firmware version https://ftp.hp.com/pub/softpaq/sp79001-79500/sp79158.exe 

Or try a Microsoft System Restore point prior to the last update which seems to have caused this problem.

Or you now have a hardware problem. 

[Prophicy]

I do have this in my device manager not sure what that is either. I just did a fresh install of win10 and nothing has been plugged into it yet.

When I run the old firmware you sent I get this:

【Upgrading】Search touch device...

This touch panel IC firmware update is for ILITEK only. We identified your
touch panel IC is not ILITEK. Please ignore this firmware update program and exit this program.
This touch panel IC firmware update is for ILITEK only.
Please ignore this firmware update program and exit this program.

[Bill_To]

Hi

Run HP UEFI Hardware Diagnostics. I am leaning towards a hardware failure since you did a clean W10 install. Did you install all Windows updates?

The Device Descriptor Request Failed error should not appear immediately after installing and updating Windows. This error suggests Windows is unable to identify the device. This is why you can't install the Touch Panel firmware.

[Prophicy]

I ran it and everything came up clean, but I didn't see test for anything touch related other than the pen and mouse diagnostics. 

Not saying you're wrong and this may be a dumb question. But the screen works perfectly fine other than the touch HID, what hardware am I troubleshooting the screen itself or the motherboard?

[Bill_To]

Hi @Prophicy 

Video and touch are two different MB functions.

You have three failure points:

The MB USB controller

The serial cable connecting the motherboard to the touch screen

The touch screen

Device Manager shows "USB Device Descriptor Request Failed". Device Manager errors usually occur when Windows detects the hardware but can't install the correct driver. There would be no Device Manager error message if the MB controller has failed. This leads me to believe the integrated MB controller (USB in this situation) is okay. But Windows does not know how to use the hardware.

Also, you can't install the Touch Panel firmware that is needed to use the device. I don't think you mentioned any Device Manager errors in Human Interface Devices. You may not see an error here because this device has failed.

I can only conclude the serial cable has a problem or the touch screen has failed. I could be wrong. But you do have a hardware problem in one or more of the three variables needed to use the touch screen functions.

A local PC tech would have to isolate the bad component.