XZ Premium Touchscreen Issues - Motherboard Problem?

[avdgfc]

Hi.  Just looking for a bit of advice on a touchscreen issue.  I have two XZ Premiums one that i've owned from new and another that I bought for spares/repairs.  One black / one chrome.

Both display/touchscreens work fine when one of the motherboards is installed (the original i've owned from new).

However when I plug the second motherboard in (from the spares/repairs phone) the display works but no touchscreen at all, whether installed in the black or chrome handset.

The query I have is what/where on the motherboard could be causing touchscreen calibration issues i.e. any of the board connectors or ports?  I'm almost certain the touchscreen issues are motherboard related but just looking to see if anyone has experienced similar issues before?

Thanks

[Lord_viridis]

If only one board has the issue in both displays, that would tell me that the touch controller on that board is faulty.

Not an easy fix at all.

[CosmicTomato]

Yeah LordViridis is right, maybe try the touchscreen tests in either of the devices with the second motherboard installed, and check if there could be anything detected.

[avdgfc]

Thanks both.  The second board has developed the same fault now unfortunately.  Conceded defeat and going to buy a new phone and just bin these two XZ Premiums.

I've had sony flagships the last 10 years T, Z3+ and then the XZ Premium but seriously considering moving brands.  All of my problems started with a B2B charging problem which is apparently clear to the hundreds of forum posts/messages you see people sticking on about phone only charging under pressure.

Do I risk £900+ for a Xperia 1 ii only for it to become a complete waste/wreck in two years time?  Very tough one.