Pull over and park when it's safe to do so and shut the engine off before any damage is done. Contact your trusted mechanic for diagnoses.
The light is not a coolant light, it is a temperature light which comes on when the temperature of the coolant is above the limits. In other words you engine is overheating. Can be defective thermostat, bad water pump, clogged radiator, or blown head gasket.
engine coolant
In most vehicles there are different temperature readings, especially in newer vehicles. The TEMP light usually means the Coolant temperature in the radiator. If a warning light comes on it usually means your vehicle is overheating and should be checked out by a mechanic asap.
If you are talking about the low coolant light then it is just low of coolant. If you are talking about the coolant temperature light, then the engine is overheating. This car is 7 years old. Have the cooling system serviced. Drain the coolant and flush the system. Install a new thermostat, and add a 50/50 mix of antifreeze and distilled water.
It comes on automatically. If it is not on, the warning light comes on and the failure should be investigated.
possibly the water pump
The check gage light comes on if your engine coolant temperature is high , the oil pressure is low , or the gas tank is almost empty
Check coolant level in coolant recovery tank and radiator
See "Related Questions" below for the same discussion in the Windstar category - equally applies to the Freestar/Monterey
No , the CHECK " GAGE " light comes on if the gas gauge is at or near empty , the engine coolant temperature is HIGH , or the engine oil pressure is LOW
I was looking at the 2004 Ford Explorer Owner Guide and it has a picture of a instrument panel that shows a " check gage " light in the upper left corner by the engine coolant temperature gauge . The light comes on if the engine coolant temperature is high , the engine oil pressure is low , or ( the fuel gauge is at or near empty )
Likely a faulty coolant temperature sensor. Change the sensor.