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:
Trip odometers
Trip odometers and reset button
1 Odometer display
2 Button for toggling between T1 and T2,
and for resetting the odometer
The trip odometers are used to measure short
distances. A short pres ...
Repairing stone chips
1. Place a strip of masking tape over the damaged
surface. Pull the tape off so that any
loose flakes of paint adhere to it.
2. Thoroughly mix the primer and apply it with
a small brush.
3. ...
Turn signal indicator – trailer (certainmodels)
If you are towing a trailer, this
light
will flash simultaneously with the
turn signals on the trailer. If the
light does not flash when signaling,
neither the trailer's turn signals nor
the ve ...
