Toyota 2004 Prius Owner's Manual page 126

(a) Discharge Warning Light
This light warns that the auxiliary battery
is being discharged.
If it comes on while you are driving, there
is a problem somewhere in the charging
system.
The hybrid system will continue to oper-
ate, however, until the auxiliary battery is
discharged. Turn off the air conditioning,
blower, radio, etc., and drive directly to
the nearest Toyota dealer or repair shop.
126
(b) Low Engine Oil Pressure Warning
Light
This light warns that the engine oil pres-
sure is too low.
If it stays on while you are driving, pull
off the road to a safe place and stop the
engine immediately. Call a Toyota dealer
or qualified repair shop for assistance.
The light may come on when the oil level
is extremely low. It is not designed to
indicate low oil level, and the oil level
must be checked using the level dipstick.
NOTICE
Do not drive the vehicle with the
warning light on—even for one block.
It may ruin the engine.
(c) High Coolant Temperature
Warning Light
The light operates to warn that the hybrid
system is almost overheating.
If it comes on while you are driving, stop
the vehicle and check your hybrid system.
For detailed instructions, see "If your ve-
hicle overheats" on page 242.
Your vehicle may overheat during severe
operating conditions, such as:
D
Driving up a long hill on a hot day.
D
Reducing speed or stopping after high
speed driving.
NOTICE
z Do not remove the thermostat in
the cooling system as this may
cause the hybrid system to over-
heat. The thermostat is designed to
control the flow of coolant to keep
the temperature of the hybrid sys-
tem within the specified operating
range.
z Continued driving with the light on
could result in the overheating of
hybrid system.