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:
Limitations
Even if a fairly small section of the screen image appears to be obstructed,
this may mean that a relatively large area behind the vehicle is hidden and objects
there may not be detected until the ...
Replacing the battery in the remote key
The batteries should be replaced if:
The information symbol illuminates and Low battery in remote control. Please
change batteries. is shown in the display and/or
if the locks do not react af ...
Brake Support
If the risk of collision continues to increase after the collision warning has
been given, Brake Support is activated. Brake Support prepares the brake system
to react quickly, and the brakes are ...
