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DTC P0464 FUEL LEVEL SENSOR CIRCUIT INTERMITTENT

DTC P0464 FUEL LEVEL SENSOR CIRCUIT INTERMITTENT

OUTLINE OF DIAGNOSIS

Detect the malfunction of unstable output from fuel level sensor caused by noise.

Judge NG when the max. value and cumulative value of output voltage variation of fuel level sensor is larger than the threshold value.

ENABLE CONDITION

Secondary Parameters Enable Conditions
Engine speed

≥ 500 rpm

After engine starting

1 second or more

Ignition switch

ON

Battery voltage

> 10.9 V

Idle switch

ON

Fuel level

9.0 ←→ 51 litres (10.1 ←→ 50.7 US gal, 8.4 ←→ 42.2 Imp gal)

Vehicle speed = 0 km/h (0 MPH)

10 seconds or more



GENERAL DRIVING CYCLE


Perform the diagnosis continuously in idling condition.

Pay attention to the fuel level.


DIAGNOSTIC METHOD

Calculate the Max. value (delflmax) and cumulative value (sumfl) of output voltage variation of fuel level sensor during 12.2 seconds. Judge it normal when both max. and cumulative values are not over the threshold value. Otherwise, when either of them is over the threshold value, count the diagnosis counter up. And judge NG if the counter indicated 4 counts.


Abnormality Judgment

Judge NG when the malfunction criteria below are completed.

Judgment Value

Malfunction Criteria Threshold Value
Integrated times of the condition reaching follows,

DELFLMAX ≥ 0.2 ←→ 0.26 V or SUMFL ≥ 16 V

where,

DELFLMAX is Max. deviation of sensor output during 12.2 seconds.

SUMFL is integrated value of sensor output deviation during 12.2 seconds.

≥ 4 times



Do not count the diagnosis counter up when the following conditions are completed during 12.3 seconds.

Max − Min of tank pressure during 12.2 seconds

≥ 0.05 kPa (0.375 mmHg, 0.02 inHg)

Max − Min of battery voltage during 12.2 seconds

≥ 0.465 V



Time Needed for Diagnosis: 12.2 seconds × 4 times

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

Normality Judgment

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

Judgment Value

Malfunction Criteria Threshold Value
DELFLMAX

< 0.2 ←→ 0.26 V

SUMFL

Where, DELFLMAX is Max. deviation of sensor output during 12.2 seconds. SUMFL is integrated value of sensor output deviation during 12.2 seconds.

< 16 V



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 OPERATION AT DTC SETTING

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