Toyota 2003 Prius Owner's Manual page 101

(a) Brake System Warning Light and
Buzzer
This light comes on in the following cases
when the ignition key is in the "ON" posi-
tion.
D
When the parking brake is applied...
This light comes on for a few seconds
when the ignition key is turned to the
"ON" position even after the parking brake
is released.
D
When the brake fluid level is low...
CAUTION
It is dangerous to continue driving
normally when the brake fluid level is
low.
D
When the regenerative brake system
is fails...
D
When the hydraulic brake booster
fails...
If the hydraulic booster causes a problem
resulting in poor braking performance, the
warning light comes on and buzzer sounds
continuously.
94
Have your vehicle checked
Toyota dealer in the following cases:
D
The light does not come on even if the
parking brake is applied when the igni-
tion key is in the "ON" position.
D
The light does not come on even if the
ignition key is turned on with the park-
ing brake released.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If any of the following conditions oc-
curs, immediately stop your vehicle at
a safe place and contact your Toyota
dealer.
D
The light does not turn off even
after the parking brake is released
while the hybrid system is running.
D
The warning buzzer comes on to-
gether with the warning light.
In either case, this can indicate that
the brakes may not work properly and
your stopping distance will become
longer. Depress the brake pedal firmly
and bring the vehicle to an immediate
stop.
at your
D
The brake system warning light re-
mains on together with the "ABS"
warning light.
In this case, not only the anti–lock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
Any of the following conditions may oc-
cur, but do not indicate the malfunc-
tion:
D
The light may stay on for about 60
seconds after the ignition key is turned
to the "ON" position. It is normal if it
turns off after a while.
D
Depressing the brake pedal repeatedly
may turn on the warning light and
buzzer. It is normal if the light turns off
and the buzzer stops sounding after a
few seconds.
D
You may hear a small sound in the
engine compartment after the hybrid
system is started or the brake pedal is
depressed repeatedly. This is a pump
pulsating sound of the brake system,
and it is not a malfunction.