Fault code P2185 G83 2010 JETTA TDI

Hello,
This afternoon coming from work,the check engine light came on. Checking fault code with vcds it showed below fault code.
How difficult it is to change the temperature sensor? From what I read, there could be a second temperature sensor, does that one need to be changed too?
Lastly, could this issue be covered under Dieselgate warranty?
Thank you in advance for the help..
1 Fault Found:
008581 - Engine Coolant Temp Sensor on Radiator Outlet (G83)
P2185 - 000 - Signal too High - Intermittent - MIL ON
Freeze Frame:
Fault Status: 10100000
Fault Priority: 2
Fault Frequency: 2
Reset counter: 255
Mileage: 363741 km
Time Indication: 0
Date: 2050.14.22
Time: 17:05:15
Freeze Frame:
RPM: 1196 /min
Speed: 71.0 km/h
Temperature: 43.2°C
Temperature: 76.5°C
Temperature: -29.7°C
Temperature: 50.4°C
Temperature: 42.3°C

Well, I have replaced the G83 coolant temp sensor with the identical one bought from the dealer, and made the matter somehow worse. Now the moment the key is on, the fans runs at high speed continuously. Before replacement of the sensor the engine light was off but the fault code was still present, but now the mil is on and fans running non stop with the same fault code.
I am taking to the dealer tomorrow. Will let you know the outcome.

I got the car from the dealer this morning. One of the wire from the G83 sensor (connected to main engine wiring harness) was broken not allowing the signal--or current-go through. The dealer replaced the wire and associated connector.
Now it runs fine, but even though MIL indicated the code P2185, the G83 coolant sensor was actually OK.