Diagnostic Method
Integrate the difference of faf in every 128 milliseconds and difference of lambda value.
After integrate 1640 times (210 seconds), calculate the diagnosis value.
Judge NG when the malfunction criteria below are completed. Judge OK and clear NG when the malfunction criteria below are not completed.
Judgment Value
JUDGMENT VALUE
| Malfunction Criteria | Threshold Value |
|---|---|
| parafca = td2faf/td2lmd where, | > 0.325 |
| td2faf (N) = td2faf (n-1) + |d2faf (n)| | |
| td2lmd (N) = td2lmd (n-1) + |d2lmd (n)| | |
| add up for a total of 300 seconds | |
| d2faf (n) = (faf (n) - faf (n-1)) - (faf (n-1) - faf (n-2)) | |
| d2lmd (n) = (lmd (n) - lmd (n-1)) - (lmd (n-1) - lmd (n-2)) | |
| faf = main feedback compensation coefficient every 128 milliseconds | |
| lmd = output lambda every 128 milliseconds |
Time Needed for Diagnosis: 210 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.