Coming back from the beach later in the evening, so I turned on my nav lights + dash lights,and headed out. Look down at the engine temperature and it says 210
Slowed down and fiddled around a bit and I figured out that when I turned on my dash lights, the voltage (via dash meter) drops from 12V to 10V, which causes the funky high temp reading. Voila, turn off the dash lights = engine temp back to 170 as normal.
My dash volt meters really don't read correctly, they say 12V while underway and it should be more like 13.8 - 14.4V. But I expect the voltage drop was real enough and caused the temperature gauge to give an false reading?
Anyone seen this before and any ideas why this would happen?