Originally Posted by imag

Water temp gauges have been disconnected from true water temps for years now on most cars - it doesn't surprise me that this is the same. They want people to feel comforted about the car and not get stressed when coolant temps fluctuate, so they basically fix it in a middle position once it comes up to temp. It only goes higher if it get out of range.

Anyway, I know most other car manufacturers do this - not sure if Nissan did it in the 370, but it sounds like it.