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Checking Monitor Status

  1. INTRODUCTION 

    The Monitor Status (mode 6) allows the OBD scan tool to display the monitor result, the test value and test limit (malfunction criterion). A Problem in the emission-related components such as the catalyst, EVAP and thermostat can be found by comparing the test value and test limit. The monitor status information is included under "MONITOR RESULT" in the emissions-related DTC sections.

    The ECM (PCM) monitors the emissions-related components. After the monitor, the ECM stores the monitor result and test value. The monitor result indicates whether the component is functioning normally or not (PASS or FAIL). The test value is the value that was used to determine the monitor result. When the test value is inside the test limit, the ECM determines the component is functioning normally (PASS). If the test value is outside the test limit, the ECM determine the component is malfunctioning (FAIL).

  2. PROCEDURE 
    NOTE: The monitor results and test value are cleared when the ignition switch is turned OFF. 
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch and hand-held tester ON.
    3. Clear the DTCs.
    4. Run the vehicle in accordance with the applicable drive pattern described in READINESS MONITOR DRIVE PATTERN  (See READINESS MONITOR DRIVE PATTERN  ).
    5. Select from the tester menus: DIAGNOSIS, ENHANCED OBD II, MONITOR INFO and MONITOR RESULT. The monitor result appears after the component name.
      • INCMP: The component has not been monitored yet.
      • PASS: The component is functioning normally.
      • FAIL: The component is malfunctioning.
    6. Confirm that the component is set to either PASS or FAIL.
    7. Select the component and press ENTER. The accuracy test value appears when the monitor result is either PASS or FAIL.
    8. Compare the test value with the MIN and MAX values (test limits). If the test value is between the MIN and MAX values (test limits), the component is functioning normally. If not, the component is malfunctioning. The test value is usually significantly higher or lower than the test limits. If the test value is on the borderline of the test limit, there is a potential malfunctioning in the component.

      HINT:

      The monitor result might on rare occasions be PASS even if the malfunction indicator lamp (MIL) is illuminated. This indicates the system malfunctioned on a previous driving cycle. This might be caused by an intermittent problem.

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