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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2012 Volvo S60 Review
Before test-driving the 2012 Volvo S60, I considered Volvos to be functional
cars that included cutting-edge safety features. Put another way, I thought
Volvos were dutifully practical family cars ...
Introduction
System overview
Cell phone
Location of the microphone
Steering wheel keypad
Center console control panel and display
...
Changing wheels
Location of the jack
The jack is located in the center under the rear
hatch in the cargo area floor. Lift this hatch and
release the retaining strap to slide out the jack.
The rear section of th ...
