The vehicle must be on a level surface when checking the coolant level.
It is normal to see coolant moving in the upper coolant hose return line when the engine is running.
Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down.

If coolant is visible but the coolant level is not at or above the mark pointed to, add a 50/50 mixture of clean drinkable water and DEX-COOL coolant.
Be sure the cooling system is cool before this is done.
What to Use
How to Add Coolant to the Coolant Surge TankInsuring the Vehicle
Protect your investment in the GM vehicle with comprehensive and collision insurance
coverage. There are significant differences in the quality of coverage afforded
by various insurance policy terms.
Many insurance policies provide reduced protection to the GM vehicle by limiting
compensation ...
TPMS Malfunction Light
The TPMS will not function properly if one or more of the TPMS sensors are missing
or inoperable. When the system detects a malfunction, the low tire warning light
flashes for about one minute and then stays on for the remainder of the ignition
cycle. The malfunction light comes on at each ign ...
Engine Compartment Fuse Block
The engine compartment fuse block is on the driver side of the vehicle, near
the battery.
Caution
Spilling liquid on any electrical component on the vehicle may
damage it. Always keep the covers on any electrical component.
To access the fuses, press the tab at the front of the cover, and ...