This stupid light came on and off in the past but only briefly on selected COLD days. Now in the summer this light ocmes on everytime I start the car and won't turn off until I get the car moving for about a few minutes. Is an indication I have to change the coolant? Or change the radiator fan at all? What must be done here?

Add 50/50 coolant to 15 mm above the max line and you should be fine. In addition, if you park on a slope, park facing downhill rather than uphill.

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The light is simply an indication that the sensor in the tank isn't seeing the coolant at the proper level.

If the tips that tony provided don't turn off the light, the sesnor may be contaminated or may have failed.

Steve

I've seen cases where the lights indicates... Low coolant, weak coolant, loss in pressure.