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System Status (I/M 240)

Typical OBD II Drive Cycle:






System Status and Drive Cycle For Satisfying Federal Inspection/Maintenance (I/M 240) Regulations.
The "System Status" selection is included in the scan tool System Info menu.

Several states require that the IM 240 (OBD II system) pass on-board tests for the major diagnostics prior to having a vehicle emission inspection. This is also a requirement to renew license plates in some areas.

Using a scan tool, the technician can observe System Status (complete or not complete) to verify that the vehicle meets the criteria to comply with local area requirements. Using the System Status display, any of the following systems or combination of systems may be monitored for I/M Readiness:

- The three-way catalytic converter
- Heated Oxygen Sensors (HO2S)
- HO2S Heaters
- EGR System
^ The fuel trim system

Following a DTC info clear, System Status will be cleared only for the systems affected by any DTCs stored. Following a battery disconnect or a PCM replacement, all System Status information will be cleared.


NOTE: The System Status display indicates only whether or not the test has been completed and does not necessarily mean that the test has passed. If a "Failed Last Test" indication is present for a DTC associated with one of the above systems, that test is failed; diagnosis and repair is necessary to meet the I/M 240 requirement. Verify that the vehicle passes the all of the diagnostic tests associated with the displayed System Statuses prior to returning the vehicle to the customer. Refer to the Typical OBD-II Drive Cycle image (more than one drive cycle may be needed) to use as a guide to complete the I/M 240 System Status tests.