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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Reinserting the key blade in the remote key
1. Hold the remote key with the slot for the key blade up.
2. Carefully slide the key blade into its groove.
3. Gently press the key blade in the groove until it clicks into place. ...
The alarm indicator light
The status of the alarm system is indicated by the red indicator light on the
dashboard (see illustration):
Indicator light off – the alarm is not armed
The indicator light flashes at one-se ...
Introduction
Information display and controls
1 READ–press to acknowledge/confirm/erase a message)
2 Thumb wheel (used to scroll among the trip computer menus)
3 RESET–resets certain functions
To scroll thro ...
