iPad 6

Problem DescriptionSymptomsSolutionSource
Not charging, no power.- If you have a tristar tester or lightning breakout board you should test that before attempting the following.

- Test with a known good battery.

- Replace charge port.

- If the above didn’t help you likely have a dead tristar.
Source
Intermittent display issue.No backlight or no display at all.For whatever reason, the 5662 backlight IC dies over time and causes the intermittent no display issue and/or a total loss of display. Replacing this chip fixes the issue.Source
Touch issues.- May be ghost touching.

- Touch may randomly stop working during use.
- It’s very easy to damage the digitizer FPC connector on the board. Inspect it for physical damage.

- Another common issue on this model is solder balls cracking under the touch ICs, usually reflowing them is enough to fix, if not then replace them.

- If the above does not fix the issue, it’s likely some of the traces between the touch ICs and FPC connector are broken internally. There isn’t a reliable fix for this.
Source