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.
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Exterior
Chief Designer Peter Horbury calls the XC90’s appearance “masculine, but not
macho; muscular, but not aggressive.” At 188.9 inches long overall, the XC90 is
3.4 inches longer than Volvo’s V70 wago ...
Fault tracing and actions
If the message Windscreen Sensors
blocked is displayed, this means that the camera
is obscured and cannot detect pedestrians,
vehicles or road marker lines in front of the
vehicle.
This, in t ...
Bluetooth version information
This feature offers information about the
Bluetooth version installed in the vehicle's
infotainment system. This information can be
found under Bluetooth menu
Bluetooth
software version in ...
