Toyota Lexusc Owner's Handbook Manual page 102

NOTICE
D Do not remove the thermostat in the engine cooling
system as this may cause the engine to overheat. The
thermostat is designed to control the flow of coolant
to keep the temperature of the engine within the
specified operating range.
D Do not continue driving with an overheated engine.
See "If your vehicle overheats" on page 495.
GAUGES, METERS AND SERVICE REMINDER INDICATORS
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