AUTOMATIC TRANSAXLE SYSTEM DIAGNOSIS SYSTEM


  1. M-OBD


    1. When troubleshooting Multiplex On-Board Diagnostic (M-OBD) vehicle, the vehicle must be connected to the intelligent tester. Various data output from the TCM can then be read.

    2. A01CF93E03

      OBD regulations require that the vehicle's on-board computer illuminates the MIL on the instrument panel when the computer detects a malfunction in:


      1. The emission control system/components

      2. The powertrain control components (which affect vehicle emissions)

      3. The computer

        In addition, the applicable DTCs are recorded in the TCM memory.

        If the malfunction does not reoccur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain recorded in the TCM memory.

    3. To check DTCs, connect the intelligent tester to the Data Link Connector 3 (DLC3) of the vehicle. The intelligent tester displays DTCs, freeze frame data and a variety of engine data.

      The DTCs and freeze frame data can be cleared with the intelligent tester Click here.

  2. NORMAL MODE AND CHECK MODE


    1. 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.

  3. 2 TRIP DETECTION LOGIC


    1. When a malfunction is first detected, the malfunction is temporarily stored in the TCM memory (1st trip). If the same malfunction is detected during the next drive cycle, the MIL is illuminated (2nd trip).

  4. FREEZE FRAME DATA


    1. The TCM 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.

    2. A01CDBAE01

      The intelligent tester records freeze frame data in 5 different instances: 1) 3 times before the DTC is set, 2) once when the DTC is set, and 3) once after the DTC is set. These sets of data can be used to simulate the vehicle conditions around the time when the malfunction occurred. The data may help in finding the cause of the malfunction, or in judging if the DTC was caused by a temporary malfunction.

  5. CHECK DATA LINK CONNECTOR 3 (DLC3)


    1. Check the DLC3 Click here

  6. BATTERY VOLTAGE


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

  7. CHECK MIL


    1. 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 Click here.

    2. When the engine is started, the MIL should turn off.