On-Board Diagnostic System Description

WARNING: This page is about a different car, the 2003 Suzuki XL-7. However, it is still accessible from the selected car via links, so may be relevant.

ECM in this vehicle in compliance with OBD-II regulations, has following functions:

When ignition switch is turned to ON position, MIL illuminates as a bulb check of the MIL.
When ECM detects a malfunction which would have an adverse effect on vehicle emissions while engine is running, MIL flashes (flashes only when detecting a misfire which can cause damage to the catalyst). ECM stores DTC in memory. If after 3 driving cycles ECM no longer detects condition that set DTC, MIL is turned off. DTC will remain stored in memory.
As a condition for detecting a malfunction, in some areas system being monitored by ECM, 2 drive cycle detection logic is adopted to prevent erroneous detection.
When a malfunction is detected, engine and driving conditions then are stored in ECM memory as freeze frame data. (For the details, refer to description on Freeze frame data.)
It is possible to communicate with ECM by using Suzuki scan tool, or OBD-II generic scan tools which are in compliance with SAE J1978. (Diagnostic information can be accessed by using a scan tool.)