Diagnostic Method

After the enable conditions have been established, calculate the front oxygen (A/F) sensor lambda value deviation sum value (Σ |(sglmd_n - sglmd_{n_1} )|), and rear oxygen sensor output voltage deviation sum value (Σ |(ro2sad_n - ro2sad_n-1 )|) in every 32 ms x 4 times. If the front oxygen (A/F) sensor lambda value deviation sum value (Σ |(sglmd_n - sglmd_n-1 )|) is the predetermined value or more, calculate the judgment value.

• Abnormality Judgment 

  If the duration of time while the following conditions are met is within the time indicated, judge as NG.

Time Needed for Diagnosis:  30 - 55 seconds

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

• Normality Judgment 

  Judge as OK and clear the NG if the continuous time while the following conditions are established is within the predetermined time.

Time Needed for Diagnosis:  30 - 55 seconds