If you're looking to repair your tether, the link below may help you fix common issues.
If your tether is inside your sensor
To get started you will need to have access to the tether. If you don't have access, you can disassemble your sensor by:
1) Take out the top screws with an Allen wrench
2) Use a USB cable to push down the charging port and pull up the case
3) Disconnect wires
4) Lift the rest of the unit from the base to access the tether
5) Follow the video below for the rest of the fix
If you have access to your tether