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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Operation
Controls and display
1 Resume previous settings, increase speed (each additional press increases
speed by 1 mph (approximately 2 km/h).
2 Standby mode on/off
3 Set time interval
4 Put in activ ...
On and off
To switch Collision Warning on or off, press MY CAR on the center console control
panel and go to Settings Car settings Driver support systems Collision Warning.
If Collision Warning is on, the sy ...
Safety
Safety is the key quality of any Volvo. Ever since the first Volvo was built
in 1927, the overriding priority has been to develop cars that help prevent
accidents and, if the accident does happen, ...
