SFI SYSTEM - DIAGNOSIS SYSTEM
When troubleshooting Europe On-Board Diagnostic (Euro-OBD) vehicles, the vehicle must be connected to an OBD scan tool (complying with ISO 15765-4). Various data output from the vehicle ECM can then be read.
Euro-OBD regulations require that the on-board computer of the vehicle illuminate the Malfunction Indicator Lamp (MIL) on the instrument panel when the computer detects a malfunction in:
The emission control system components
The powertrain control components (which affect vehicle emissions)
The computer itself
In addition, the applicable Diagnostic Trouble Codes (DTCs) prescribed by ISO 15765-4 are stored in the ECM memory. If the malfunction does not reoccur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain stored in the ECM memory.
To check the DTCs, connect the intelligent tester to the Data Link Connector 3 (DLC3) of the vehicle. The scan tool displays DTCs, the freeze frame data and a variety of the engine data. The DTCs and freeze frame data can be cleared with the scan tool.
| M-OBD (EXCEPT EUROPEAN SPEC.) |
When troubleshooting Multiplex On-Board Diagnostic (M-OBD) vehicle, the vehicle must be connected to the intelligent tester. Various data output from the ECM can then be read.
OBD regulations require that the on-board computer of the vehicle illuminate the MIL on the instrument panel when the computer detects a malfunction in:
The emission control system components
The powertrain control components (which affect vehicle emissions)
The computer
In addition, the applicable DTCs are stored in the ECM memory. If the malfunction does not recur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain stored in the ECM memory.
| NORMAL MODE AND CHECK MODE |
The diagnosis system operates in normal mode during normal vehicle use. In normal mode, 2 trip detection logic is used to ensure accurate detection of malfunctions. Check mode is also available as an option for technicians. In check mode, 1 trip detection logic is used for simulating malfunction symptoms and increasing the ability of the system to detect malfunctions, including intermittent problems (intelligent tester only).
When a malfunction is first detected, the malfunction is temporarily stored in the ECM memory (1st trip). If the same malfunction is detected during the next subsequent driving cycle, the MIL is illuminated (2nd trip).
The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
- Standard voltage:
- 11 to 14 V
If voltage is below 11 V, replace or recharge the battery before proceeding.
| MIL (Malfunction Indicator Lamp) |
The MIL is illuminated when the engine switch is first turned on (IG) (the engine is not running).
The MIL should turn off when the engine is started. If the MIL remains illuminated, the diagnosis system has detected a malfunction or abnormality in the system.
- If the MIL is not illuminated when the engine switch is first turned on (IG), check the MIL circuit ().
With "All Readiness" it is possible to check whether or not the DTC judgment has been completed by using the intelligent tester.
Check "All Readiness" after simulating malfunction symptoms or for validation after finishing repairs.
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Perform the DTC judgment driving pattern to run the DTC judgment.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTCs to be confirmed.
Check the DTC judgment result.
Result| Tester Display | Description |
| NORMAL | DTC judgment completed
System normal
|
| ABNORMAL | DTC judgment completed
System abnormal
|
| INCOMPLETE | DTC judgment not completed
Perform driving pattern after confirming DTC enabling conditions
|
| N/A | Unable to perform DTC judgment
Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
|
