WARNING
Never adjust the instrument cluster while driving. This could result in loss of control and lead to an accident that may cause death, serious injury, or property damage.

The brightness of the instrument panel illumination changes by pressing the upper or lower part of the switch when the ignition switch is in the ON position and when the parking lights are turned on.

If the brightness reaches to the maximum or minimum level, a chime will sound (if equipped).
Instrument cluster
GaugesHyundai Creta GS 2014-2019 Service Manual: Troubleshooting
Troubleshooting
Symptom
Suspect area
Engine will not start or struggle to start
Vapor hose damaged or disconnected
Engine struggles to start
Malfunction of the Purge Control Solenoid Valve
...
Hyundai Creta GS 2014-2019 Service Manual: Seat Belt Buckle Switch (BS)
Description and operation
Description
Buckle Sensor (BS) sends driver/passenger seat belt fastened/unfastened status
signal to the Smart Junction Box (SJB). If either side seat belt is unfastened,
the warning lamp is turned ON in the Cluster, and turned OFF when the seat belt ...