Toyota Verso-S Manual page 501

NOTICE
 When adding engine coolant
Wait until the engine has cooled down before adding engine coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot engine too
quickly can cause damage to the engine.
 To prevent damage to the cooling system
Observe the following precautions:
 Avoid contaminating the coolant with foreign matter (such as sand or dust
etc.).
 Do not use commercially available coolant additives.
VERSO-S_EE
5-2. Steps to take in an emergency
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