SFI SYSTEM > DIAGNOSIS SYSTEM

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DESCRIPTION
If the malfunction does not recur in 3 consecutive trips, the MIL goes off automatically but the DTCs remain recorded in the ECM (Included in HV Control ECU) memory.

  1. FI02547
    When troubleshooting Euro-OBD vehicles, the only difference from the usual troubleshooting procedure is that you connect an OBD scan tool (complying with ISO 15031-4) or an intelligent tester to the vehicle, and read the various data output from the vehicle's ECM.
  2. Euro-OBD regulations require that the vehicle's on-board computer illuminates the MIL (Malfunction Indicator Lamp) on the instrument panel when the computer detects a malfunction in: 1) the emission control systems and components, 2) the powertrain control components (which affect vehicle emissions), or 3) the computer. In addition, the applicable DTCs (Diagnostic Trouble Codes) prescribed by ISO 15031-4 are recorded in the ECM (Included in HV Control ECU) memory.
  1. To check the DTCs, connect the OBD scan tool or intelligent tester to the DLC3 (Data Link Connector 3) on the vehicle. The OBD scan tool or intelligent tester also enables you to erase the DTCs and check the freeze frame data and various forms of engine data. (See the instruction manual for the OBD scan tool or intelligent tester.)

  2. E109221E03
    *2 trip detection logic: When a malfunction is first detected, the malfunction is temporarily stored in the ECM (Included in HV Control ECU) memory (1st trip). If the ignition switch is turned OFF and then to ON again, and the same malfunction is detected again, the MIL illuminates (2nd trip).
  3. Freeze frame data: The ECM (Included in HV Control ECU) 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.

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 system's ability to detect malfunctions, including intermittent problems (intelligent tester only).

2 TRIP DETECTION LOGIC
  1. When a malfunction is first detected, the malfunction is temporarily stored in the ECM (Included in HV Control ECU) memory (1st trip). If the same malfunction is detected during the next subsequent drive cycle, the MIL is illuminate (2nd trip).

FREEZE FRAME DATA
  1. Freeze frame data record the engine conditions (fuel system, calculated engine load, engine coolant temperature, fuel trim, engine speed, vehicle speed, etc.) when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

DLC3 (Data link Connector 3)

  1. A082779E01
    The vehicle's ECM uses the ISO 9141-2 (Euro-OBD) for communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-3 and matches the ISO 9141-2 format.

Symbols
Terminal No.
Names
Reference terminal
Results
Condition
SIL
7
Bus "+" line
5 - Signal ground
Pulse generation
During transmission
CG
4
Chassis ground
Body ground
1 Ω or less
Always
SG
5
Signal ground
Body ground
1 Ω or less
Always
BAT
16
Battery ground
Body ground
9 to 14 V
Always
CANH
6
CAN "High" line
CANL
54 to 69 Ω
Ignition switch OFF
CANH
6
CAN "High" line
Battery positive
1 MΩ or higher
Ignition switch OFF
CANH
6
CAN "High" line
CG
1 kΩ or higher
Ignition switch OFF
CANL
14
CAN "Low" line
Battery positive
1 MΩ or higher
Ignition switch OFF
CANL
14
CAN "Low" line
CG
1 kΩ or higher
Ignition switch OFF

HINT:
The DLC3 is the interface prepared for reading various data from the vehicle's ECM (Included in HV Control ECU). After connecting the cable of an intelligent tester, turn the ignition switch on and turn the tester ON. If a communication failure message is displayed on the tester screen, a problem exists in either the vehicle side or tester side. In order to identify the location of the problem, connect the tester to another vehicle.
  1. If communication is normal: Inspect the DLC3 on the original vehicle.
  2. If communication is still not possible: The problem is probably in the tester itself. Consult the Service Department listed in the instruction manual.


BATTERY VOLTAGE

Battery Voltage:
11 to 14 V

  1. If voltage is below 11 V, replace or recharge the battery before proceeding.

MIL (Malfunction Indicator Light)

  1. The MIL is illuminated when the engine switch is first turned on (the engine is not running).

  2. The MIL should turn OFF when the engine is started. If the MIL remains illuminated, the diagnosis system has detected malfunction or abnormality in the system.

    HINT:
    If the MIL is not illuminated when the engine switch is first turned to on, check the MIL circuit (Click here).