Coolant low light is on. What do I need to do?

If your coolant reservoir is full and the low coolant light is on, it is probably your coolant level sensor. If your low coolant light is on, and your reservoir is low....your are loosing coolant somewhere.

It's actually a message. It will say "Low coolant level" or "Check coolant level" . Hard to miss. Anyway, the sensor is in and part of the coolant reservoir. If the sensor isn't working, you need to replace the reservoir.

The coolant type is not the issue but It seems there is a LOW LEVEL OF the COOLANT. Allow the engine to cool down and check the coolant level in the overflow/reservoir tank. If low you need to top up the coolant in the tank. Also check the pressure cap of the radiator, replace if there is low level of coolant in the radiator.
However if the coolant looks murky or rusty then it is best to flush out the coolant and refill with the specified type.

Low coolant doesnt have anything to do with the thermostat. If the coolant bottle was over filled, it will push out, it needs some air space. only fill it to the full line. If the low coolant light is on, but its not really low, the sensor may be bad. Be sure to use the correct coolant DEXCOOL.

reset the computer, if no change, replace the coolant sensor, but after reset it should work

I think your buick has a pressure coolant system so you may have air in the system and need too bleed it and for the light coming on while on the highway most likely low coolant when your driving the higher rpm the more coolant is drawn into the motor and triggering the light from coolant reservoir running low on coolant

U will need to replace the low coolant sensor or try cleaning the one that is there now, they get coolant deposits on them and cause a false low coolant light/warning

there are no fuses for that. there is a sensor on the coolant tank that senses when you need to add antifreeze. Check for coolant level and add if low if not low you need a new sensor.

Low coolant means just that, find out if the system is really low or the light is receiving a false signal from the low coolant sensor, just check the level in the coolant recovery tank and the make sure the radiator tank is full, if you are low on coolant then check out why, a leak is probable, most likely a water pump or hose related issue, and no a bad thermostat will not in itself turn on the low coolant light unless the engine boils over and the system becomes low. Remember never ever open a radiator cap on a hot engine, you would be surprised how many professional mechanics get burned this way, be careful..

Hi Amber

This is the Low Coolant Level indicator. You may need service soon. Hopefully, you are just low, however, it could indicate other problems (minor or major).

NEVER remove the radiator cap while the coolant is HOT!

Here is info straight from your owners manual:
Low Coolant Warning Light
This light comes on
briefly when you turn
your ignition on.
If this light comes on and stays on and you hear a chime,
the vehicle should promptly be pulled off the road and
the coolant level checked.