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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Electronic climate control, ECC
Electronic climate control, ECC
1 Temperature control, driver's side
2 Heated driver's seat*
3 Defroster (maximum effect)
4 Blower
5 Manual air distribution—floor
6 Manual air distribution—das ...
Continuous wiping
The wipers operate at normal speed.
The wipers operate at high speed. ...
Windshield wipers
1 Thumb wheel
2 Rain sensor on/off
Windshield wipers off
If the lever is in the 0 position
and
you move it upwards, the wipers
will sweep one stroke at a time for
as long as you hold the lev ...
