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:
Folding down the rear seat backrests
The rear seat backrests are split and can be folded down together
or separately
1. Pull the release control handle(s).
2. Fold the backrest forward. Adjust the center seat head restraint if nece ...
Main instrument panel
Information display and menu controls
1 - READ – access to the list of messages and message confirmation.
2 - Thumbwheel – browse among menus and options in the list of functions.
3 - RESET – res ...
Checking and adding oil
Location of the filler cap and dipstick
Volvo recommends Castrol oil products
NOTE
Before checking the oil:
The car should be parked on a level surface.
If the engine is warm, wait f ...
