Towards the end of last years mowing the temp light would come on for a little while then go off. The engine didn't seem to be overheating and coolant level was good. I figured it was the sensor. I mowed for the first time today and the light came on and stayed on. I let it cool, started it and left it sitting at half idle and after a few minutes the light comes on. I have a parts 725 so I swapped sensors. Same issue. I took both sensors and tested with a meter in hot water. When cold, the needle doesn't move, shows a open circuit. When I put them in hot water, one shows 2200 ohms, the other 1000. I'm not sure what a correct reading is. Could both be bad or I have other issues?