Adjusting instrument cluster illumination

When the vehicle's parking lights or headlights are on, press the illumination control button to adjust the brightness of the instrument panel illumination.
When pressing the illumination control button, the interior switch illumination intensity is also adjusted.
WARNING
Never adjust the instrument cluster while driving. Doing so could lead to driver distraction which may cause an accident and lead to vehicle damage, serious injury, or death.

Instrument Cluster
GaugesHyundai Elantra AD (2016-2020) Service Manual: Auto Defoging Actuator Specifications
Specifications
Door positionVoltage (V)Error detectingMax. cooling0.3 ± 0.15Low voltage : 0.1V or lessMax. heating4.7 ± 0.15High voltage : 4.9V or more
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Hyundai Elantra AD (2016-2020) Service Manual: Side Airbag (SAB) Module Components and Components Location
Components
1. Side Air Bag (SAB)
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