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:
Channel lock
Access to specific channels can be restricted (locked). A locked channel will
not provide audio, song titles, or artist information.
NOTE
All channels are initially unlocked.
Locking a chann ...
Cordless headphones
1 Switch for selecting channel A (CH.A) or channel B (CH.B)
2 On/Off button
3 Volume
4 On/Off indicator light
Two sets of cordless headphones are included
with the RSE system.
The cordless he ...
Audible/visual alarm signal
• An audible alarm signal is given by a battery
powered siren. The alarm cycle lasts
for 30 seconds.
• The visual alarm signal is given by flashing
all turn signals for approximately 5 minutes ...
