Tech Tips

GTS only:

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

In check mode, the ECM sets DTCs using 1-trip detection logic.


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


    1. Make sure that the vehicle is in the following condition:

      1. Battery voltage is 11 V or more.

      2. Shift lever is in neutral.

      3. A/C is switched off.

    2. Turn the ignition switch off (where on).

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON and turn the GTS on.

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

    6. A01BHDOE09

      Make sure the MIL flashes as shown in the illustration.

    7. Start the engine (the MIL should turn off).

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

    9. Check the DTC(s) and freeze frame data using the GTS.

    10. After checking the DTC, inspect the applicable circuits.