Subaru Legacy IV (2008 year). Manual - part 413

GD(H4DOTC)-102

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BE:DTC P0413 SECONDARY AIR INJECTION SYSTEM SWITCHING VALVE “A” 

CIRCUIT OPEN

1. OUTLINE OF DIAGNOSIS

Judge as NG when the ECM output level differs from the actual terminal level.

2. ENABLE CONDITIONS

3. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

4. 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: 2500 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

Secondary Parameters

Enable Conditions

None

 

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts OFF signal

LOW

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts OFF signal

HIGH

GD(H4DOTC)-103

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BF:DTC P0414 SECONDARY AIR INJECTION SYSTEM SWITCHING VALVE “A” 

CIRCUIT SHORTED

1. OUTLINE OF DIAGNOSIS

Judge as NG when the ECM output level differs from the actual terminal level.

2. ENABLE CONDITIONS

3. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

4. 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: 2500 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

BG:DTC P0416 SECONDARY AIR INJECTION SYSTEM SWITCHING VALVE “B” 

CIRCUIT OPEN

1. OUTLINE OF DIAGNOSIS

NOTE:
For the detection standard, refer to DTC P0413. <Ref. to GD(H4DOTC)-102, DTC P0413 SECONDARY AIR
INJECTION SYSTEM SWITCHING VALVE “A“ CIRCUIT OPEN, Diagnostic Trouble Code (DTC) Detecting
Criteria.>

BH:DTC P0417 SECONDARY AIR INJECTION SYSTEM SWITCHING VALVE “B” 

CIRCUIT SHORTED

1. OUTLINE OF DIAGNOSIS

NOTE:
For the detection standard, refer to DTC P0414. <Ref. to GD(H4DOTC)-103, DTC P0414 SECONDARY AIR
INJECTION SYSTEM SWITCHING VALVE “A“ CIRCUIT SHORTED, Diagnostic Trouble Code (DTC) De-
tecting Criteria.>

Secondary Parameters

Enable Conditions

None

 

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts ON signal

HIGH

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts ON signal

LOW

GD(H4DOTC)-104

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BI: DTC P0418 SECONDARY AIR INJECTION SYSTEM CONTROL “A” CIRCUIT 

OPEN

1. OUTLINE OF DIAGNOSIS

Judge as NG when the ECM output level differs from the actual terminal level.

2. ENABLE CONDITIONS

3. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

4. 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: 2500 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

Secondary Parameters

Enable Conditions

None

 

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts OFF signal

LOW

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Ignition

ON

Terminal output voltage when ECM out-
puts OFF signal

HIGH

GD(H4DOTC)-105

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

BJ:DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1)

1. OUTLINE OF DIAGNOSIS

Detect the deterioration of the catalyst function.
Though the front oxygen sensor output would change slowly with a new catalyst, the sensor output with a de-
teriorated catalyst becomes high and the inversion time is shortened.
For this reason, the catalyst diagnosis is carried out by monitoring the front oxygen sensor output and com-
paring it with the front oxygen (A/F) sensor output.

2. COMPONENT DESCRIPTION

(A)

Normal

(C)

Output waveform from the front 
oxygen (A/F) sensor

(D)

Output waveform from the front 
oxygen sensor

(B)

Deterioration

 

 

 

 

(1)

Front oxygen (A/F) sensor

(2)

Front oxygen sensor

(3)

Catalytic converter

EN-01713

(A)

(B)

(C)

(D)

(1)

(2)

(3)

(3)