2009 hyundai sonata p2138
1996 and up have obd2
underneath the dash, above the accelerator
under the dash on the right of the drivers side
The connector is under the dash although a little harder to see. Hyundai will not release the code meanings for their cars, so your connecting the scanner will not give you much good information.
The OBD2 connector is located underneath the ash tray.
OBD2
In my 2004 Chevy Aveo LS, the OBD-II connector is against the panel closest to the driver's knees above the brake pedal.
Right side of the drivers footwell, between the steering wheel and dash.
It's located under the driver's side instrument panel
All OBD2 connectors on 2004 vehicles of any make are found on the left (drivers) side under the dash panel. Most have covers to protect the prongs.
Driver's side footwell. Scroocth under the steering column and look up. You'll see the connector near the steering column.