Diagnostic Method

Calculate faf difference every 32ms x 4, and the λ value difference. Calculate the diagnosis value after calculating 1640 time(s).

• Abnormality Judgement 

  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	0.4 (U5 model)
  	0.45 (Other than U5 model)
  where,
  td2faf (N) = td2faf (n-1) + |d2faf (n)|
  td2lmd (N) = td2lmd (n-1) + |d2lmd (n)|
  add up to 32 ms x 4 x 1640 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 1640 time(s)

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

• Normality Judgement 

  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	≤ 0.4 (U5 model)
  	≤ 0.45 (Other than U5 model)
  where,
  td2faf (N) = td2faf (n-1) + |d2faf (n)|
  td2lmd (N) = td2lmd (n-1) + |d2lmd (n)|
  add up to 32 ms x 4 x 1640 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 1640 time(s)