Equus 3130 - Scan Tool – OBD2 - Manual (Page 31)

OBD2 29
E
Using the Scan Tool
I/M READINESS TESTING
■ If the erase was not successful, an
advisory message shows on the dis-
play. Verify that the Scan Tool is prop-
erly connected to the vehicle’s DLC
and that the ignition is on, then
repeat steps 2 and 3, above.
Erasing DTCs does not fix the problem(s) that caused the
code(s) to be set. If proper repairs to correct the problem that
caused the code(s) to be set are not made, the code(s) will
appear again (and the check engine light will illuminate) as
soon as the vehicle is driven long enough for its Monitors to
complete their testing.
I/M READINESS TESTING
I/M is an Inspection and Maintenance program legislated by the
Government to meet federal clean-air standards.
The program requires that a vehicle be taken periodically to an
Emissions Station for an "Emissions Test" or "Smog Check,” where the
emissions-related components and systems are inspected and tested
for proper operation. Emissions Tests are generally performed once a
year, or once every two years.
On OBD 2 systems, the I/M program is enhanced by requiring vehicles to
meet stricter test standards. One of the tests instituted by the Federal
Government is called I/M 240. On I/M 240, the vehicle under test is driv-
en under different speeds and load conditions on a dynamometer for 240
seconds, while the vehicle's emissions are measured.
Emissions tests vary depending on the geographic or region-
al area in which the vehicle is registered. If the vehicle is reg-
istered in a highly urbanized area, the I/M 240 is probably the
type of test required. If the vehicle is registered in a rural area,
the stricter “dynamometer type” test may not be required.
I/M Readiness Monitors
I/M Readiness shows whether the various emissions-related systems
on the vehicle are operating properly and are ready for Inspection and
Maintenance testing.
State and Federal Governments enacted Regulations, Procedures and
Emission Standards to ensure that all emissions-related components
and systems are continuously or periodically monitored, tested and
diagnosed whenever the vehicle is in operation. It also requires vehi-
cle manufacturers to automatically detect and report any problems or
faults that may increase the vehicle's emissions to an unacceptable level.
The vehicle's emissions control system consists of several compo-
nents or sub-systems (Oxygen Sensor, Catalytic Converter, EGR, Fuel
System, etc.) that aid in reducing vehicle emissions.