How do states use OBD II for emission inspections?

Many states connect a computer directly to a vehicle's OBD II system. The inspector can then read "faults." In some states, this type of inspection has replaced the tailpipe emission test.
See also:
Lighting panel
Overview, light switches
1 - Thumb wheel for adjusting display and instrument lighting
2 - Rear fog light
3 - Headlights/parking lights
Instrument lighting
Illumination of the display and instr ...
Limitations
NOTE
• The sound source (AM, FM1, Disc,
etc.) being played through the infotainment
system's speakers cannot be controlled
from the rear control panel.
• In order to select and play an externa ...
Front park assist
The distance monitored in front of the vehicle
is approximately 2.5 ft (0.8 m). The audible signal
comes from the audio system's front
speakers.
It may not be possible to combine auxiliary
...
