Battery issues, original battery held a 40 min charge.
After initially replacing the battery I began testing the unit and found that Bluetooth had a slight but major problem.
When I used Bluetooth to play music through wireless headsets or any of my cars apps like Apple Music or hey Siri worked flawlessly. I was even able to use FaceTime via a Bluetooth connected device without a problem.
When I attempted to make an audio call using my mobile carrier the sound became silent both ways. The receiver and myself did not hear a thing.
The problem was an issue with screw placement. Within the iPhone 5s there is a shield that protects connections that is located by the front camera and is held down by four screws.
These four screws have two configurations, two screws are slightly longer than the other.
In order for Bluetooth audio to function, the shorter screws must be placed on the bottom half of the wires shield nearest to the home button.
After replacing the screw configuration, I am pleased to report Bluetooth operates normally.
Fed up using a wired headset configuration, I searched the internet quite aggressively and after a week of searching for the problem found the resolution via the apple supprt website.
Before I resolved the issue, I had performed the following:
System format software with new download (deleted hidden iTunes software update, reset phone, have iTunes up and hold menu button down then plug lightning cable while connected to computer)
Deleted and reconnected Bluetooth devices on both phone and Bluetooth speakers (car/headset)