The instrument panel vent air flow can be directed up/down or left/right using the vent adjustment lever.
The air flow can also be closed using the vent adjustment lever. To close the instrument panel vents, slide the vent adjustment lever to the LEFT until it clicks.
Hyundai Elantra AD (2016-2020) Service Manual: Front Door Module Components and Components Location
Component Location
1. Front door module
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Hyundai Elantra AD (2016-2020) Service Manual: Front Bumper Cover Components and Components Location
Component Location
1. Front bumper cover
...