Hyundai NEXO 2019 Owner's Manual page 407

What to do in an emergency
6. If you cannot find the cause of the
overheating, wait until the radiator
temperature has returned to nor-
mal. Then, if coolant has been
lost, carefully add coolant to the
reservoir to bring the fluid level in
the reservoir up to the halfway
mark.
7. Proceed with caution, keeping
alert for further signs of overheat-
ing. If overheating happens again,
call an authorized HYUNDAI deal-
er for assistance.
CAUTION
Serious loss of coolant indi-
cates a leak in the cooling sys-
tem and should be checked as
soon as possible by an author-
ized HYUNDAI dealer.
6-10