DTC P0452: Evaporative Emission Control System Pressure Sensor Low Input

OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the fuel tank pressure sensor.

Judge NG when out of the standard value.
COMPONENT DESCRIPTION

Fig 1: DTC P0452 - Evaporative Emission Control System Pressure Sensor Low Input - Component Description
Courtesy of SUBARU OF AMERICA, INC.

ENABLE CONDITION (USED WITH HIGH SIDE NORMAL/ABNORMAL JUDGMENT)

ENABLE CONDITION CHART

Secondary Parameters	Enable Conditions
Battery voltage	"GREATER THAN EQUAL TO" 10.9 V

DIAGNOSTIC METHOD

Abnormality Judgment

Judge NG when the continuous time of completing the malfunction criteria below becomes more than 15 seconds.

Judgment Value

JUDGMENT VALUE CHART

Malfunction Criteria	Threshold Value
Fuel tank pressure	< -7.33 kPa (-55 mmHg, -2.17 inHg)

Time Needed for Diagnosis: 15 seconds

Malfunction Indicator Light Illumination: Illuminates as soon as malfunction occurs.

Normality Judgment

Judge OK when the malfunction criteria below is completed.

Judgment Value

JUDGMENT VALUE CHART

Malfunction Criteria	Threshold Value
Fuel tank pressure	"GREATER THAN EQUAL TO" 7.33 kPa (-55 mmHg, -2.17 inHg)
Feedback lambda coefficient	"GREATER THAN EQUAL TO" 0.9

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
Purge control solenoid valve control: Purge fixation mode is prohibited.
ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)