Chevrolet 2001 Impala Owner's Manual page 161

Low Coolant Level
United States
This message is displayed when the cooling system is
low on coolant. Four chimes will also sound.
The engine may overheat. See "Engine Coolant" in the
Index and have your vehicle serviced as soon as you can.
Low Oil Pressure
Canada
This message is displayed when the engine oil
pressure is low. A chime will sound continuously, also.
See "Low Oil Pressure Light" earlier in this section.
United States Canada
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