Dodge Challenger SRT 2016 Owner's Manual page 149

Dimmer Controls
The dimmer control is part of the headlight switch and is
located on the left side of the instrument panel.
Dimmer Controls
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 147
With the parking lights or headlights on, rotating the left
dimmer control upward will increase the brightness of
the instrument panel lights and lighted cupholders (if
equipped).
Instrument Panel Dimmer
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