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Diagnostic Method

Calculate faf difference every 32 ms x 4, and the λ value difference. Calculate the diagnosis value after calculating 820 time(s).

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

Judgement Value 

JUDGEMENT VALUE REFERENCE

Malfunction Criteria Threshold Value
parafca = td2faf/td2lmd 0.22
where,  
td2faf (N) = td2faf (n-1) + |d2faf (n)|  
td2lmd (N) = td2lmd (n-1) + |d2lmd (n)|  
add up to 32 ms x 4 x 820 time(s).  
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:  32 ms x 4 x 820 time(s)

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

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

Judgement Value 

JUDGEMENT VALUE REFERENCE

Malfunction Criteria Threshold Value
parafca = td2faf/td2lmd ≤ 0.22
where,  
td2faf (N) = td2faf (n-1) + |d2faf (n)|  
td2lmd (N) = td2lmd (n-1) + |d2lmd (n)|  
add up to 32 ms x 4 x 820 time(s).  
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:  32 ms x 4 x 820 time(s)