Chevrolet 1995 Lumina Owner's Manual page 219

If this light comes on, it
means you're low on engine
coolant.
To Add Coolant
If you need more coolant, add the proper mix at the
coolant recovery tank.
If the coolant recovery tank is completely empty, add
coolant to the radiator. (See "Engine Overheating" in the
Index.)
Add coolant mix at the recovery tank, but be careful not
to spill it.
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