Dash Temperature guage intermittent Mk6 Transit

[CasualNerd]

Just wondering if anyone has some suggestions about where to start looking...

The temperature gauge sometimes shows a reasonable temp and sometimes drops out completely. I assume it's either faulty wiring / joins or the sensor is dying. As far as I can see fuses are all good etc.

Much rather find this myself than head to the local garage as they'll probably take hours to trace it back. So is there a likely fail point ?