How much does it cost to replace a sensor light? A red light has come on my dash stating coolant is low, check coolant. The coolant was checked and it was okay, not low
Sensor light for coolant levels on 2001 Buick Century
The coolant reservoir sensor may just be stuck. I would try flushing out the coolant reserve tank to free up the sensor, if that does not work, you can get a new sensor from GM for about $50.