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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Stage 2: Checking inflation pressure
1. Connect the tire sealing system as described
in stage 1.
2. Refer to the inflation pressure table in this
chapter for the correct inflation pressure. If
the tire needs to be inflated, start ...
Introduction
Collision Warning with Full Auto-brake and
Pedestrian Detection is designed to assist the
driver if there is a risk of a collision with a
pedestrian, a vehicle ahead that is at a standstill
or ...
Engine compartment, overview
The appearance of the engine compartment
may vary depending on engine model.
1 Coolant expansion tank
2 Power steering fluid reservoir
3 Engine oil dipstick
4 Radiator
5 Filler cap for engine ...
