2004 Toyota Prius Owners Manual - Page 138

(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 operate, 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. (b) Low Engine Oil Pressure Warning Light This light warns that the engine oil pressure 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. (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 vehicle 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 Do not drive the vehicle with the warning light on-even for one block. It may ruin the engine. NOTICE z Do not remove the thermostat in the cooling system as this may cause the hybrid system to overheat. The thermostat is designed to control the flow of coolant to keep the temperature of the hybrid system within the specified operating range. z Continued driving with the light on could result in the overheating of hybrid system. 126