Diagnostic Method

• Abnormality Judgment 

Judge as NG if the criteria below are met.

Judgment Value 

Timer for diagnosis after engine start

1. Timer stop at fuel cut
2. During the driving conditions except a) above, timer counts up as follows.

   64 ms + TWCNT ms (at 64 ms)

   TWCNT is defined as follows,

   TWCNT = 0 at idle switch ON,

   TWCNT show on the following table at idle switch OFF.

   VEHICLE SPEED SPECIFICATION
   
   

   		Vehicle speed km/h (MPH)
   		0 (0)	8 (5)	16 (9.9)	24 (14.9)	32 (19.9)	40 (24.9)	48 (29.8)	56 (34.8)
   Temperature °C (°F)	-20 (-4)	0 ms	37.136 ms	74.272 ms	111.41 ms	126.66 ms	141.91 ms	163.59 ms	185.26 ms
   	-10(14)	0 ms	27.391 ms	54.782 ms	82.173 ms	99.65 ms	117.13 ms	135.96 ms	154.8 ms
   	0 (32)	0 ms	17.646 ms	35.292 ms	52.938 ms	72.64 ms	92.341 ms	108.34 ms	124.33 ms
   	10 (50)	0 ms	7.9012 ms	15.802 ms	23.704 ms	45.63 ms	67.556 ms	80.711 ms	93.867 ms
   	20 (68)	0 ms	7.9012 ms	15.802 ms	23.704 ms	45.63 ms	67.556 ms	80.711 ms	93.867 ms

   Judgment value of timer after engine starting

   t = 451056 ms - 25870 ms x Ti

   Ti: The lowest coolant temperature after engine start

   Time Needed for Diagnosis:  Less than 1 second

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

   • Normality Judgment 

   Judge as OK and clear the NG when the malfunction criteria below are met.

   Judgment Value 

   JUDGMENT VALUE
   
   

   Malfunction Criteria	Threshold Value
   Engine coolant temperature	≥ 20 °C (68 °F)

   Time Needed for Diagnosis:  Less than 1 second