iPad Air 4

Problem Description	Symptoms	Solution	Source
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
No touch.		- Test with a known good display. - Can be caused by a defective cap in the touch circuit. Look for shorts around the FPC and touch IC.	Source