Lexus IS250 IS220d GSE20 ALE20 - A960E AUTOMATIC TRANSMISSION
AUTOMATIC TRANSMISSION SYSTEM - DIAGNOSIS SYSTEM
| 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 the 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 the engine data.
The DTCs and freeze frame data can be erased with the scan tool .
| M-OBD (EXCEPT EUROPEAN SPEC.) |
When troubleshooting Multiplex On-Board Diagnostic (M-OBD) vehicles, the vehicle must be connected to the 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 to, the applicable DTCs 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.
| 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 engine switch is turned off and then turned on again, and the same malfunction is detected again, the MIL will illuminate.
| FREEZE FRAME DATA |
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.
The intelligent tester displays freeze frame data recorded at five different points: 1) 3 times before the DTC is set, 2) once when the DTC is set, and 3) once after the DTC is set. The data can be used to simulate the vehicle's condition around the time of the malfunction. The data may be helpful in determining the cause of a malfunction. It may also be helpful in determining whether a DTC is being caused by a temporary malfunction.
| DLC3 (Data Link Connector 3) |
The vehicle's ECM uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-03 and matches the ISO 15765-4 format.
- HINT:
- Connect the cable of the intelligent tester to the DLC3, turn the engine switch on (IG) and attempt to use the intelligent tester. If the screen displays a communication error message, a problem exists in the vehicle side or the tester side.
If the communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
If the communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself. Consult the Service Department listed in the tool's instruction manual.
| Symbols (Terminal No.) | Terminal Description | Condition | Specified Condition |
| SIL (7) - SG (5) | Bus "+" line | During transmission | Pulse generation |
| CG (4) - Body ground | Chassis ground | Always | Below 1 Ω |
| SG (5) - Body ground | Signal ground | Always | Below 1 Ω |
| BAT (16) - Body ground | Battery positive | Always | 9 to 14 V |
| CANH (6) - CANL (14) | HIGH-level CAN bus line | Ignition switch OFF | 54 to 69 Ω |
| CANH (6) - Battery positive | HIGH-level CAN bus line | Ignition switch OFF | 1 MΩ or higher |
| CANH (6) - CG (4) | HIGH-level CAN bus line | Ignition switch OFF | 1 kΩ or higher |
| CANL (14) - Battery positive | LOW-level CAN bus line | Ignition switch OFF | 1 MΩ or higher |
| CANL (14) - CG (4) | LOW-level CAN bus line | Ignition switch OFF | 1 kΩ or higher |
| CHECK BATTERY VOLTAGE |
- Battery voltage:
- 11 to 14 V
If voltage is below 11 V, replace the battery before proceeding.
| CHECK MIL |
Check that the MIL illuminates when turning the engine switch on (IG).
If the MIL does not illuminate, there is a problem in the MIL circuit .
When the engine is started, the MIL should turn off.
| ALL READINESS |
For this vehicle, using the intelligent tester allows readiness codes corresponding to all DTCs to be read. When diagnosis (normal or malfunctioning) has been complete, readiness codes are set.