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:
Instrument panel lighting
The instrument panel lighting illuminates when
the ignition key is in position II and the light
switch (1) is in either position
Move the thumb wheel (4) up to increase
brightness or down to decr ...
Washing the car
The following points should be kept in mind
when washing and cleaning the car:
• The car should be washed at regular intervals
since dirt, dust, insects and tar spots
adhere to the paint and ma ...
Fuel filler cap
The fuel filler door, located on the right rear
quarter panel, is connected to your vehicle's
central locking system. ...
