Temperture needle behaving erratic Ducati 916 bp

After a weekend away with the bike I noticed the front headlight bulb had blown. When I returned home and on the way to work I noticed the temp gauge behaving abnormal. The gauge would normally settle above 140 when warm and rise. On the way to work, I noticed the gauge drop below 140 after it was warm and stay down nearly returning to cold, yet the bike was at normal temperature as I had covered some 10 miles of motorway.
Later I took the panels off and cleaned the bike. I noticed the battery levels were low again, having been topped up only a couple of weeks previous. I then thought there might be a regulator rectifier issue. I Posted on the ducatisti forum and with some suggestions and thinking again. Decided to disconnect the connector to the rectifier. Below you can see that under the plastic connector there has been a build up, indicating a dirty connection. I cleaned the connector and recharged the battery. The battery was registering 12v1 and thought this was a bit low. I replaced the front headlight bulb and rear brake light switch that was faulty. The brake light switch could have been draining the battery. This did not cure the issue
so i took apart all the connectors in the headlamp and removed the clocks. I have now found out that the regulator rectifier was faulty as it was cooking the battery. I noticed readings of 17volts which was too much for the battery. I have fitted another one of another bike which has three wires on the connecter. Although still working as it should regulating the voltage.

Now the bike seems to be behaving correctly. The temp gauge moves in a normal fashion.