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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Cleaning the interior
Only use cleaning agents and car care products recommended by Volvo. Clean regularly
and follow the instructions included with the car care product.
Upholstery care
Fabric
Clean with soapy water ...
Limitations
Main channel vs. sub-channels (FM only): The main channel is the only channel
that can receive in hybrid mode (both digital and analogue). If a frequency
has subchannels, they are broadcast i ...
Location of the keyless drive antennas
The keyless drive system has a number of antennas located at various points in
the vehicle.
1 - On the inside center of the rear bumper
2 - Left rear door handle
3 - Center of the parcel shelf, ...
