On-Board Diagnostic (OBD) System Description: Notes
ECM in this vehicle has the following functions.
- When the ignition switch is turned to ON position with the engine stopped, malfunction indicator lamp (MIL) (1) turns on in order to check the MIL (1) and its circuit.
- When ECM detects a malfunction which gives an adverse effect to vehicle emission more than specified driving cycle (D/C), it turns on or flashes MIL in the combination meter (flashing only when detecting a misfire which can cause damage to the catalyst) and stores the diagnostic trouble code (DTC) in its memory.
(If it detects normal condition for continuously 3 driving cycles after detecting a malfunction, it turns off MIL although DTC stored in its memory is remained as a history DTC.)
- For some malfunctions, ECM adopts the 2 D/C detecting logic to prevent erroneous detection. With this logic, MIL is turned on when the malfunction is detected in 2 consecutive driving cycles.
- Malfunctions detected by ECM are stored in its memory as pending DTC, confirmed DTC (current and history) and permanent DTC.
The permanent DTC, among others, will be stored in the memory that cannot be manually erased. (For the details, refer to description on PERMANENT DTC (EVAP LEAK CHECK MODEL) .)
- When a malfunction is detected, engine and driving conditions at that moment are stored in ECM memory as freeze frame data.
For details, refer to description on FREEZE FRAME DATA .
- It is possible to communicate ECM via data link connector (DLC) (3) not only by SUZUKI scan tool (SUZUKI-SDT) (2) but also by CAN communication OBD generic scan tool.