Manual

  Using the Diagnostic Tool 
  I/M READINESS TESTING 
OBD2 53 
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 OBD2 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 driven 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 
regional area in which the vehicle is registered. If the vehicle 
is registered 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 
vehicle 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 components 
or sub-systems (Oxygen Sensor, Catalytic Converter, EGR, Fuel 
System, etc.) that aid in reducing vehicle emissions. 
To have an efficient Vehicle Emission Control System, all the emissions-
related components and systems must work correctly whenever the 
vehicle is in operation. 
To comply with State and Federal Government regulations, vehicle 
manufacturers designed a series of special computer programs called 
"Monitors" that are programmed into the vehicle's computer. Each of 
these Monitors is specifically designed to run tests and diagnostics on a 
specific emissions-related component or system (Oxygen Sensor, 
Catalytic Converter, EGR Valve, Fuel System, etc.) to ensure their 
proper operation. Currently, there are a maximum of eleven Monitors 
available for use. 










