DTC P0181: Fuel Temperature Sensor "A" Circuit Range/Performance

Detect the malfunction of fuel temperature sensor output property.

Perform the diagnosis in two methods; namely, drift diagnosis and stuck diagnosis. Judge NG when either of them results in NG, and judge OK when both of them result in OK.

• 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 make an NG judgment.

Always perform the diagnosis continuously.

• Abnormality Judgment 

  Judge NG when the continuous time of completing the malfunction criteria below becomes more than 120 seconds.

  Judgment Value 

  JUDGMENT VALUE CHART
  
  

  Malfunction Criteria	Threshold Value
  Fuel level	"GREATER THAN EQUAL TO" 10 ° (2.64 US gal,
  2.20 lmp gal)
  After engine starting	20 seconds or more
  Engine coolant temperature - engine coolant temperature at engine starting	> 10°C (18°F)
  Fuel temperature - engine coolant temperature	"GREATER THAN EQUAL TO" 10°C (18°F)
  Battery voltage	< 10.9 V

  Time Needed for Diagnosis:  120 seconds

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

• Normality Judgment 

  Judge OK when the malfunction criteria below are completed.

  Judgment Value 

  JUDGMENT VALUE CHART
  
  

  Malfunction Criteria	Threshold Value
  Fuel level	"GREATER THAN EQUAL TO" 10 ° (2.64 US gal, 2.20 lmp gal)
  After engine starting	20 seconds or more
  Engine coolant temperature - engine coolant temperature at engine starting	< 10°C (18°F)
  Fuel temperature - engine coolant temperature	"GREATER THAN EQUAL TO" 10°C (18°F)
  Battery voltage	< 10.9 V

• Stuck Diagnosis 

If the fuel temperature which might rise along with the engine idling (the cumulative amount of intake air after engine starting is large) does not increase, the engine is considered to be stuck and make an NG judgment.

Perform the diagnosis continuously in 20 seconds or more after starting the engine.

• Abnormality Judgment 

  Judge NG when the malfunction criteria below are completed.

  Judgment Value 

  JUDGMENT VALUE CHART
  
  

  Malfunction Criteria	Threshold Value
  Accumulated amount of intake air	"GREATER THAN EQUAL TO" 550 kg (1212.5 lb)
  Fuel temperature difference between Max. and Min.	< 3°C (5.4°F)

  Time Needed for Diagnosis:  To be determined.

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

• Normality Judgment 

  Judge OK when the malfunction criteria below are completed.

  Judgment Value 

  JUDGMENT VALUE CHART
  
  

  Malfunction Criteria	Threshold Value
  Accumulated amount of intake air	"GREATER THAN EQUAL TO" 550 kg (1212.5 lb)
  Fuel temperature difference between Max. and Min.	"GREATER THAN EQUAL TO" 3°C (5.4°F)

• DTC CLEAR CONDITION 
  • When the OK idling cycle was completed 40 times in a row
  • When "Clear Memory" was performed
• MALFUNCTION INDICATOR LIGHT CLEAR CONDITION 
  • When the OK driving cycle was completed 3 times in a row
  • When "Clear Memory" was performed
• FAIL SAFE 

  None

• ECM OPERATING AT DTC SETTING 

  Memorize the freeze frame data. (For test mode $02)