Subaru Legacy IV (2008 year). Manual - part 420

GD(H4DOTC)-130

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BP:DTC P0452 EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE 

SENSOR LOW INPUT

1. OUTLINE OF DIAGNOSIS

Detect the open or short circuit of the fuel tank pressure sensor.
Judge as NG if out of specification.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

(A)

Output voltage

(B)

Input voltage

(C)

To fuel tank

(1)

Connector

(2)

Terminals

Secondary Parameters

Enable Conditions

None

 

EN-04462

(A)

(B)

(2)

(1)

(C)

GD(H4DOTC)-131

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

5. DIAGNOSTIC METHOD

• Abnormality Judgement

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

Time Needed for Diagnosis: 15000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.

• Normality Judgement

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

Judgement Value

Malfunction Criteria

Threshold Value

Fuel tank pressure

< –7.4 kPa (–55.85 mmHg, 
–2.2 inHg)

Battery voltage

t 10.9 V

Judgement Value

Malfunction Criteria

Threshold Value

Fuel tank pressure

t –7.4 kPa (–55.85 mmHg, 
–2.2 inHg)

Battery voltage

t 10.9 V

GD(H4DOTC)-132

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BQ:DTC P0453 EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE 

SENSOR HIGH INPUT

1. OUTLINE OF DIAGNOSIS

Detect the open or short circuit of the fuel tank pressure sensor.
Judge as NG if out of specification.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE

Perform the diagnosis when purging enable conditions are met without idling.

(A)

Output voltage

(B)

Input voltage

(C)

To fuel tank

(1)

Connector

(2)

Terminals

Secondary Parameters

Enable Conditions

Time needed for all secondary parame-
ters to be in enable conditions

t 5000 ms

Vehicle speed

t 2 km/h (1.2 MPH)

All conditions of EVAP canister purge

Completed

Learning value of evaporation gas con-
centration (left and right)

< 0.08 

Main feedback compensation coefficient 
(left and right)

t 0.9 

Battery voltage

t 10.9 V

EN-04462

(A)

(B)

(2)

(1)

(C)

GD(H4DOTC)-133

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

5. DIAGNOSTIC METHOD

• Abnormality Judgement

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

Time Needed for Diagnosis: 15000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.

• Normality Judgement

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

BR:DTC P0456 EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECTED 

(VERY SMALL LEAK)

1. OUTLINE OF DIAGNOSIS

NOTE:
For the detection standard, refer to DTC P0442. <Ref. to GD(H4DOTC)-108, DTC P0442 EVAPORATIVE
EMISSION CONTROL SYSTEM LEAK DETECTED (SMALL LEAK), Diagnostic Trouble Code (DTC) De-
tecting Criteria.>

BS:DTC P0457 EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECTED 

(FUEL CAP LOOSE/OFF)

1. OUTLINE OF DIAGNOSIS

NOTE:
For the detection standard, refer to DTC P0442. <Ref. to GD(H4DOTC)-108, DTC P0442 EVAPORATIVE
EMISSION CONTROL SYSTEM LEAK DETECTED (SMALL LEAK), Diagnostic Trouble Code (DTC) De-
tecting Criteria.>

Judgement Value

Malfunction Criteria

Threshold Value

Fuel tank pressure

t 8 kPa (59.85 mmHg, 
2.4 inHg)

Fuel temperature

< 35 °C (95 °F)

Barometric pressure

t 75 kPa (563 mmHg, 
22.2 inHg)

Judgement Value

Malfunction Criteria

Threshold Value

Fuel tank pressure

< 8 kPa (59.85 mmHg, 
2.4 inHg)