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.
See also:
How BLIS functions in daylight and darkness
Daylight
BLIS reacts to the shape of surrounding vehicles.
The system is designed to help detect
motor vehicles such as cars, trucks, buses,
motorcycles, etc.
Darkness
BLIS reacts to the headl ...
Check coolant level
The cooling system must be filled with coolant
and not leak to operate at maximum efficiency.
Check the coolant level regularly. The level
should be between the MAX and MIN marks
on the expansio ...
Getting Around
The C30 is a fun car to drive. It has a 227-horsepower, turbocharged
five-cylinder engine that makes 236 pounds-feet of torque, which is a lot of
power for such a small car. It's estimated to get ...
