Lexus 2013 IS250 Owner's Manual page 100

NOTICE

To prevent damage to the engine and its components

Do not let the indicator needle of the tachometer enter the red zone, which
indicates the maximum engine speed.

The engine may be overheating if the engine coolant temperature gauge is in
the red zone (H). In this case, immediately stop the vehicle in a safe place, and
check the engine after it has cooled completely. (P. 530)
IS250_EE(OM53B11E)
2. Instrument cluster
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