Toyota PRIUS Owner's Manual page 527

Coolant
The coolant level is satisfactory if it is between the "FULL" and "LOW"
lines on the reservoir when the hybrid system is cold.
Engine coolant reservoir
■
Reservoir cap
1
"FULL" line
2
"LOW" line
3
If the level is on or below the
"LOW" line, add coolant up to
the "FULL" line. (→P. 649)
Power control unit coolant reservoir
■
Reservoir cap
1
"FULL" line
2
"LOW" line
3
If the level is on or below the
"LOW" line, add coolant up to
the "FULL" line. (→P. 649)
PRIUS_OM_OM47A31E_(EE)
6-3. Do-it-yourself maintenance
527
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