Toyota Avalon Hybrid 2018 Owner's Manual page 347

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
"F" line
2
"L" line
3
If the level is on or below the "L"
line, add coolant up to the "F"
line. (→P. 429)
■
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. 429)
6-3. Do-it-yourself maintenance
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