Diagnostic Method
Abnormality Judgment
Judge as NG when the malfunction criteria below are met.
Judgment Value
| Malfunction Criteria | Threshold Value |
|---|---|
| Engine coolant temperature | < 20°C (68°F) |
| Timer for diagnosis after engine starting | ≥ Judgment value of timer after engine starting |
Timer for diagnosis after engine starting
- Timer stop at fuel cut mode.
- During the driving conditions except a) above, timer count up by 64 milliseconds + TWCNT milliseconds at every 64 milliseconds.
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 (4.97) | 16 (9.94) | 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 | 82.544 ms | 117.209 ms | 154.214 ms | 185.206 ms |
| -10 (14) | 0 ms | 25.704 ms | 33.606 ms | 41.508 ms | 68.520 ms | 95.532 ms | 125.667 ms | 155.802 ms | |
| 0 (32) | 0 ms | 17.646 ms | 25.548 ms | 33.450 ms | 53.652 ms | 73.855 ms | 97.120 ms | 120.386 ms | |
| 10 (50) | 0 ms | 7.901 ms | 15.802 ms | 23.704 ms | 37.941 ms | 52.177 ms | 68.573 ms | 82.538 ms | |
Judgment value of timer after engine starting
t = 574 - 33 x Ti (seconds)
Ti is the lowest coolant temperature after starting the engine.
Time Needed for Diagnosis: To be determined. (It is varied by the Min. engine coolant temperature and engine conditions such as vehicle speed and engine coolant temperature.)
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
| Malfunction Criteria | Threshold Value |
|---|---|
| Engine coolant temperature | ≥ 20°C (68°F) |