Tech Tips

Compared to normal mode, check mode is more sensitive to malfunctions. Therefore, check mode can detect malfunctions that cannot be detected in normal mode.


All the stored DTCs and freeze frame data are cleared if: 1) the ECM is changed from normal mode to check mode or vice versa; or 2) the ignition switch is turned from ON to ACC or off while in check mode. Before changing modes, always check and note any DTCs and freeze frame data.


    1. Check and ensure the following conditions:

      1. Battery voltage is 11 V or higher.

      2. Throttle valve is fully closed.

      3. Shift lever is in P or N.

      4. A/C switch is off.

    2. Turn the ignition switch off.

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Engine and ECT / Utility / Check Mode.

      Powertrain > Engine and ECT > Utility
      Tester Display
      Check Mode
    7. Switch the ECM from normal mode to check mode.

    8. A001TR4E02
      *1 0.13 seconds
      *2 ON
      *3 OFF

      Check that the MIL flashes as shown in the illustration.

    9. Start the engine.

    10. Check that the MIL turns off.

    11. Simulate the conditions of the malfunction described by the customer.

    12. Check the DTCs and freeze frame data using the tester.