2008 Toyota Prius Owners Manual - Page 398

4-3. Do-it-yourself maintenance Engine/power control unit coolant The coolant level is satisfactory if it is between the "FULL" and "LOW" lines on the reservoir when the engine is cold. Engine coolant reservoir Reservoir cap 1 FULL FU L LO L W 2 LOW If the level is on or below the "LOW" line, add coolant up to the "FULL" line. FUL LOWL 3 ITY43P012 Power control unit coolant reservoir 4 1 2 Maintenance and care LL FU LOW LOW 3 ITY43P013 371 PRIUS_U_(L/O_0802)