A321 pilot reported a Hot Brake ECAM Message during cruise. Suspecting a bad sensor; the flight crew waited until closer to destination airport; requested priority handling and made a precautionary landing.

Narrative

While in cruise flight (had been in cruise for about 3+hours) received an ECAM for Hot Brakes. The number 3 temp was over 300 Degrees C. We had noticed this much earlier while conducting a system check. During the system check; we noticed the temp on #3 was much higher than the rest of the brake temps; so when we got the ECAM; it wasn't totally a surprise. We suspected that this was a bad temperature sensor and not a real thermal run away. We conferred with Company Maintenance Control and they concurred. We continue to monitor the #3 brake temp and we discussed that if it got anywhere close to 400 Degrees C; that we would act on the ECAM actions. During the descent to ZZZ; the temp increased to near 400C and we decided to requested priority handling. We gave ATC all the info. We accomplished the ECAM actions but as soon as we extended the gear; the temp read normal. We decided to cancel the priority handling status at that point. ATC Tower Controller asked if we wanted the emergency equipment still as a precaution and we agreed. After a normal landing on Runway XXL; the Fire Marshall conducted a temperature check of all the wheels and he related that all indicated normal even temperatures on all wheel's brakes. We proceeded to taxi to the Gate under normal conditions. Bad temp sensor on # 3 wheel. Aircraft had a maintenance history of it as it was pointed out by maintenance personal in ZZZ when they came to the flight deck and talked to us. Our decision to not act on the ECAM actions while at altitude proved to be the correct one. We tried to communicate with our dispatcher via SAT phone and the new 'Company' app. Neither one of them worked. Dispatcher also try and said that it wasn't working for him either. This tools are to be tested regularly to make sure they work when needed. Also ARINC (I believe the Dispatcher gave us the frequency) frequency heard us upon initial contact but by them we were too low to communicate any further and lost contact with them.