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System Status and Drive Cycle

Drive Cycle:






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 I/M 240 (OBD II system) pass several 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) in order 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 a combination of the systems may be monitored for I/M Readiness:

^ The Catalyst

^ The HO2S

^ The HO2S Heater

^ The EGR System (not all applications)

Following a DTC info clear, System Status will clear only for the systems that are affected by any DTCs that are stored. Following a battery disconnect or an ECM replacement, all of the System Status information will clear.

Important: 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 that is associated with one of the above systems, this indicates that the test is failed and that the diagnosis and repair is necessary in order to meet the I/M 240 requirement. Verify that the vehicle passes all of the diagnostic tests that are associated with the displayed System Status prior to returning the vehicle to the customer. Refer to the Typical OBD-II Drive Cycle graphic in the accompanying image (more than one drive cycle may be needed) to use as a guide in order to complete the I/M 240 System Status tests.