International Truck & Engine Co./Navistar

Accessing Diagnostic Trouble Codes
MaxxForce Engines
Using Scan Tool

Follow scan tool manufacturers instructions.

T444E Engine Control System
Less Electronic Service Tool (EST)
  1. Turn ignition On, then depress "ENGINE DIAGNOSTICS " switch located on instrument panel.
  2. If any fault codes are detected, ECM will flash " OIL/WATER" and "WARN ENGINE" lamp.
  3. "OIL/WATER" lamp will flash once to indicate beginning of active code.
  4. "WARN ENGINE" lamp will indicate the three digit fault code.
With Electronic Service Tool (EST)
  1. Turn all accessories and ignition Off.
  2. Connect Electronic Service Tool (EST) Pro-Link 9000, or equivalent to American Trucking Association (ATA) diagnostic connector located on lower lefthand side of kick panel. Reader screen should light as soon as the tool is plugged in. The ATA connector supplies power to operate the EST. The EST will automatically power up as soon as it is plugged into ATA connector. Power cord is not required and is for use only when reading non-volatile memory.
  3. Turn ignition On, but do not start engine. EST should start to receive data from electronic control components. If no data is received, press "ENTER" key on EST to retry. Information received will be data showing current engine status.
  4. To access fault codes, press "FUNC" key to switch EST to main menu.
  5. From main menu screen select engine by hitting backspace key. This will cause brackets to be placed around the "ENGINE" selection, then press "ENTER."
  6. Select "DIAGNOSTIC CODES" from the next menu by pressing the down symbol until "DIAGNOSTIC CODES" appears on the screen, then press the enter key.
  7. The first option that will appear on the screen will be " ACTIVE CODES." Pressing the "ENTER" key at this time will display the first active code. Pressing the down key will display any additional active codes. If there are no active codes a " NO ACTIVE CODES" will be displayed on the screen.
  8. To access "INACTIVE CODES" press " FUNC" key. This will access the last prior menu selection. Press the down arrow key to select "INACTIVE CODES," then press the "ENTER" key to display codes. Inactive codes that have occurred prior to the last key off cycle and are now stored in memory. An active code will become inactive if the key is shutoff.
  9. Record all fault codes that are found and refer to " Diagnostic Trouble Code Interpretation" for fault code diagnosis and repair.
VT-275, VT-365, 530E, DT466E, DT570 & HT570 Engine Control System
Using Flash Codes
  1. Depress and hold self-test input (STI) switch, located on instrument panel. STI switch may also be labeled "Engine Diagnostics. "
  2. Turn ignition On.
  3. OIL/WATER lamp will flash once to indicate beginning of active DTCs.
  4. If any DTCs are detected, the WARN ENGINE lamp will then flash to indicate which code(s) are present.
Using Scan Tool

With all accessories off, connect Electronic Service Tool (EST) to the American Trucking Association (ATA) diagnostic connector. The ATA connector is located on the lower lefthand side kick panel. On school buses, it may be hidden by the body builders panel near the driver's left foot.

With the tester plugged in, turn ignition On but do not start engine. Current engine status data should be displayed. If no data is displayed, press ENTER to try again. To access diagnostic trouble codes (DTCs), press the FUNC key to switch to the main menu, then follow the menu map.