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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Starting the vehicle
Starting the engine
WARNING
Before starting, check that the seat, steering
wheel and mirrors are adjusted properly.
Make sure the brake pedal can be
depressed completely. Adjust the seat if
ne ...
Checking settings
The current Collision Warning settings can be
checked by pressing MY CAR on the center
console control panel and going to Settings
Car settings
Driver support systems
Collision Warnin ...
Pedestrian safety
The Volvo V50 Sportswagon has been designed to minimise the risk of injury to
pedestrians and cyclists in the event of an accident. The smoothly shaped front
has an energy-absorbing structure ahea ...
