Lexus GS300 1998 Owner's Manual page 307

STARTING AND DRIVING
CAUTION
While the "ABS" warning light is on, if either of the following
conditions occurs, immediately stop your vehicle at a safe
place and contact your Lexus dealer.
D The brake system warning light stays on even with the
parking brake being released.
D The brake system warning light and buzzer come on.
In either case, the brakes may not work properly. If they do
not work well, depress the brake pedal firmly.
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