1996 Buick Regal Owner's Manual - Page 245

If this light comes on, it means you're low on engine coolant. I LOW COOLANT Turning the radiator pressure cap when the engine and radiator are hot can allow steam and scalding liquids toblow out and burn you badly. With the coolant recovery tank, you almost will never have to add coolant at the radiator. Never turn the radiator pressure cap even a little when the engine and radiator are hot. -- -- Addinq Coolar A If you need more coolant, add the proper mix at the coolant recovery tank. Add coolant mix at the recovery tank, but be careful not to spill it. I If the coolant recovery tank is completely empty, add coolant to the radiator. (See "Engine Overheating"in the Index.) You can be burnedif you spill coolant on hot engine parts. Coolant contains ethylene glycol, and it will burn if the engine parts are hot a enough. Don't spill coolant on hot engine.