Using the Scan Tool
I/M READINESS TESTING
68 3160g
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 fifteen Monitors available for use.
Each Monitor has a specific function to test and diagnose only its
designated emissions-related component or system. The names
of the Monitors (Oxygen Sensor Monitor, Catalyst Monitor, EGR
Monitor, Misfire Monitor, etc.) describe which component or
system each Monitor is designed to test and diagnose.
Emissions Inspection and Maintenance (I/M) Readiness
Monitor Status Information
I/M Readiness Monitor Status shows which of the vehicle's Monitors
have run and completed their diagnosis and testing, and which ones
have not yet run and completed testing and diagnosis of their
designated sections of the vehicle's emissions system.
If a Monitor was able to meet all the conditions required to enable it
to perform the self-diagnosis and testing of its assigned engine
system, it means the monitor "HAS RUN.”
If a Monitor has not yet met all the conditions required for it to
perform the self-diagnosis and testing of its assigned engine system;
it means the Monitor "HAS NOT RUN.”
The Monitor Run/Not Run status does not show whether
or not a problem exists in a system. Monitor status only
indicates whether a particular Monitor has or has not run
and performed the self-diagnosis and testing of its
associated system.
Performing I/M Readiness Quick Check
When a vehicle first comes from the factory, all Monitors
indicate a “HAVE RUN” status. This indicates that all Monitors
have run and completed their diagnostic testing. The “HAVE
RUN” status remains in the computer's memory, unless the
Diagnostic Trouble Codes are erased or the vehicle's
computer memory is cleared.
The Scan Tool allows you to retrieve Monitor/System Status Information
to help you determine if the vehicle is ready for an Emissions Test
(Smog Check). In addition to retrieving Diagnostic Trouble Codes, the
Scan Tool also retrieves Monitor Run/Not Run status. This information is
very important since different areas of the state/country have different
emissions laws and regulations concerning Monitor Run/Not Run status.
Before an Emissions Test (Smog Check) can be performed, your
vehicle must meet certain rules, requirements and procedures legislated
by the Federal and state (country) governments where you live.