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:
Switching BLIS on and off
BLIS is automatically activated when the ignition is switched on. The indicator
lights will provide confirmation by flashing 3 times.
The system can be switched off by pressing the BLIS button ...
Safety
All-disc antilock brakes, traction control, side-impact and side curtain-type
airbags, and Volvo's Whiplash Protection Seating System are standard. Dynamic
Stability and Traction Control is option ...
Checking tire pressure
Cold tires
Inflation pressure should be checked when the
tires are cold.
The tires are considered to be cold when
they have the same temperature as the surrounding
(ambient) air.
This tempera ...
