Low Coolant Light

[killerRIDESbyME]

I have a 2002 Sierra Denali , 6.0L . Occasionally the ' LOW COOLANT ' light comes on . I have checked the coolant level , it's A-OK . The TEMP gauge has never gone above about 190 . Any thoughts ?? Thermostat ? Water pump ? Sensor ?

[bossier62guy]

I have a 2002 Sierra Denali , 6.0L . Occasionally the ' LOW COOLANT ' light comes on . I have checked the coolant level , it's A-OK . The TEMP gauge has never gone above about 190 . Any thoughts ?? Thermostat ? Water pump ? Sensor ?

 

My vote is for the reservoir....sensor is located at the bottom of it. You'll have to replace the reservoir as a unit.