SFI SYSTEM > DIAGNOSIS SYSTEM

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EURO-OBD

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's ECM can then be read.

Euro-OBD regulations require that the vehicle's on-board computer illuminates the Malfunction Indicator Lamp (MIL) on the instrument panel when the computer detects a malfunction in:

The emission control system components.
The power train control components (which affect vehicle emissions).
The computer

In addition, the applicable Diagnostic Trouble Codes (DTCs) prescribed by ISO 15765-4 are recorded in the ECM memory. If the malfunction does not reoccur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain recorded in the ECM memory.

To check DTCs, connect an intelligent tester or OBD scan tool to the Data Link Connector 3 (DLC3) of the vehicle.

The scan tool displays DTCs, the freeze frame data and a variety of engine data.

The DTCs and freeze frame data can be cleared using the scan tool (Click here).

M-OBD

When troubleshooting a Multiplex On-Board Diagnostic (M-OBD) vehicle, the vehicle must be connected to an intelligent tester. Various data output from the ECM can then be read.
OBD regulations require that the vehicle's on-board computer illuminates the MIL on the instrument panel when the computer detects a malfunction in:

The emission control system/components.
The power train control components (which affect vehicle emissions).
The computer
In addition, the applicable DTCs are recorded in the ECM memory. If the malfunction does not recur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain recorded 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 to technicians as an option. In check mode, "1-trip detection logic" is used for simulating malfunction symptoms and increasing the system's ability to detect malfunctions, including intermittent malfunctions (intelligent tester only).

2-TRIP DETECTION LOGIC

When a malfunction is first detected, the malfunction is temporarily stored in the ECM memory (1st trip). If the same malfunction is detected again after the ignition switch is turned off and then ON, the MIL will be illuminated.

DLC3 (Data Link Connector 3) (Click here)

INSPECT BATTERY VOLTAGE

If the voltage is below 11 V, replace the battery before proceeding to the next step.

Standard voltage:: 11 to 14 V

CHECK MIL

Check that the MIL illuminates when the ignition switch is turned ON.
If the MIL does not illuminate, there is a problem in the MIL circuit (Click here).
When the engine is started, the MIL should turn off.

ALL READINESS

HINT:

With "All Readiness" you can check whether or not the DTC judgment has been completed by using the intelligent tester.
You should check "All Readiness" after simulating malfunction symptoms or for validation after finishing repairs.

Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the tester on.
Clear the DTCs (Click here).
Turn the ignition switch off and wait for 30 seconds.
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.

Intelligent Tester
Tester Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed You should perform driving pattern after confirming DTC enabling conditions
UNKNOWN	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU's memory limit