Diagnostic Method

• Abnormality Judgment 

Judge as NG if the criteria below are met.

Malfunction Criteria	Threshold Value
Engine coolant temperature	< 20 °C (68 °F)
Timer for diagnosis after engine start	≥ Judgment value of timer after engine start

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 (when 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 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	32.076 ms	39.977 ms	47.879 ms	71.432 ms	95.176 ms	118.981 ms	137.941 ms
	-10 (14)	0 ms	25.704 ms	33.606 ms	41.508 ms	60.2 ms	77.955 ms	95.043 ms	114.075 ms
	0 (32)	0 ms	17.646 ms	25.548 ms	33.45 ms	46.265 ms	58.666 ms	71.105 ms	85.383 ms
	10 (50)	0 ms	7.901 ms	15.802 ms	23.704 ms	31.541 ms	39.377 ms	47.168 ms	54.72 ms
	20 (68)	0 ms	7.901 ms	15.802 ms	23.704 ms	31.541 ms	39.377 ms	47.168 ms	54.72 ms

Judgment value of timer after engine starting

t = 359969 ms - 19601 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.

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

Time Needed for Diagnosis:  Less than 1 second