DTC - General Description

DTC P0181 FUEL TEMPERATURE SENSOR "A" CIRCUIT RANGE/ PERFORMANCE

1. OUTLINE OF DIAGNOSIS
Detect faults in the fuel temperature sensor output properties.
Diagnosis is performed in two methods (drift diagnosis and stack diagnosis). If either is NG, judge as NG. If both are OK, Judge as OK and clear the NG.

Drift Diagnosis
Normally fuel temperature is lower than engine coolant temperature. When the fuel temperature becomes higher than the engine coolant temperature, the range is considered to be shifted, and judged as NG.

Stuck Diagnosis
As the engine warms up (cumulative amount of intake air after starting is large), if the fuel temperature which should rise does not, determine as being stuck and NG.

2. COMPONENT DESCRIPTION






3. ENABLE CONDITION

DRIFT DIAGNOSIS






4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

5. DIAGNOSTIC METHOD

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






Time Needed for Diagnosis: 120 sec
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.

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






Time Needed for Diagnosis: Less than 1 second

6. DTC CLEAR CONDITION
- When the OK idling cycle is completed 40 times in a row
- When "Clear Memory" is performed

7. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
- When the OK driving cycle is completed 3 times in a row
- When "Clear Memory" is performed

8. FAIL SAFE
None

9. ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)

10. ENABLE CONDITION
Stuck Diagnosis






11. GENERAL DRIVING CYCLE
Always perform diagnosis after 20 seconds have passed since the engine started.

12. DIAGNOSTIC METHOD

- Abnormality Judgment
Judge as NG when the following conditions are established.






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 if the following conditions are established.






Time Needed for Diagnosis: Less than 1 second

13. DTC CLEAR CONDITION
- When the OK idling cycle is completed 40 times in a row
- When "Clear Memory" is performed

14. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
- When the OK driving cycle is completed 3 times in a row
- When "Clear Memory" is performed

15. FAIL SAFE
None

16. ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)