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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Under the Hood
The XC70's turbocharged 2.5-liter inline-five-cylinder delivers 208
horsepower and 236 pounds-feet of torque. Volvo's standard Geartronic
five-speed-automatic transmission has a feature that permi ...
Shiftlock override
If the vehicle cannot be driven, for example because of a dead battery, the gear
selector must be moved from the P position before the vehicle can be moved3.
1 - Lift away the rubber mat on the f ...
Sensor location
• The sunlight sensor is located on the top
side of the dashboard.
NOTE
The sunlight sensor monitors which side of
the car that is most exposed to sunlight.
This can mean that the temperature m ...
