Chosen Solution
The symptoms started when trying to charge the device. Sometimes it would charge and sometimes it would not. I already tried different charging cables and plugs, using a wall outlet and a computer USB port, I’ve tried a hard restart with the home and power buttons, I’ve tried to restore (with no power this is not possible), all to no avail. I finally purchased a new lightning port and installed it. It still will not power up. I have not tried installing a new battery yet and that is my last idea. Any other suggestions would be appreciated.
If it’s not the battery, it’s likely the u2ic. If the battery doesn’t work, you should send it out to iPad Rehab iPhone 6s Battery Replacement iPhone 6s Battery