Subaru 2007 B9 Tribeca Owner's Manual page 235

7-6
Starting and operating
der federal law to implement stricter vehi-
cle emission standards to reduce air pollu-
tion from vehicles. A dynamometer is a
treadmill or roller-like testing device that
allows your vehicle's wheels to turn while
the vehicle remains in one place. Depend-
ing on the severity of a state's air pollution
problems, the states must adopt either a
"basic" or "enhanced" vehicle emission in-
spection test. Normally, a portion of the
basic emission test consists of an emis-
sion inspector inserting an analyzer probe
into the exhaust pipe of an idling vehicle
for a short period of time. States with more
severe air pollution problems are required
to adopt an enhanced vehicle emission
test. This test simulates actual driving
conditions on a dynamometer and permits
more accurate measurement of tailpipe
emitted pollution than the basic emission
test.
The U.S. Environmental Protection Agen-
cy (EPA) and states using two-wheel dy-
namometers in their emission testing pro-
grams have EXEMPTED SUBARU AWD
vehicles from the portion of the testing
program that involves a two-wheel dyna-
mometer.
There are some states that use four-wheel
dynamometers in their testing programs.
When properly used, that equipment will
not damage an AWD SUBARU vehicle.
Under no circumstances should the rear
wheels be jacked off the ground, nor
should the driveshaft be disconnected for
state emission testing.
The EPA has issued regulations for in-
specting the On-Board Diagnostic (OBD)
system as part of the state emissions in-
spection. The OBD system is designed to
detect engine and transmission problems
that might cause vehicle emissions to ex-
ceed allowable limits. These inspections
apply to all 1996 model year and newer
passenger cars and light trucks. Over 30
states plus the District of Columbia have
implemented the OBD system inspection.
The inspection of the OBD system con-
sists of a visual operational check of the
"CHECK ENGINE" warning light/malfunc-
tion indicator lamp (MIL) and an examina-
tion of the OBD system with an electronic
scan tool while the engine is running.
A vehicle passes the OBD system in-
spection if proper the "CHECK ENGINE"
warning light/MIL illumination is observed,
there is no stored diagnostic trouble
codes, and the OBD system readiness
monitors are complete.
A vehicle fails the OBD inspection if the
"CHECK ENGINE" warning light/MIL is
not properly operating or there is one or
more diagnostic trouble codes stored in
vehicle's computer with the "CHECK EN-
GINE" warning light/MIL illuminated.
A state emission inspection may reject
(not pass or fail) a vehicle if the number of
OBD system readiness monitors "Not
Ready" is greater than one. Under this
condition, the vehicle operator should be
instructed to drive his/her vehicle for a few
days to set the monitors and return for an
emission re-inspection.
Owners of rejected or failing vehicles
should contact their SUBARU Dealer for
service.