Content .. 347 348 349 350 ..

Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 349

GD(H4DOTC)-148

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

CJ: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 Judgment
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 Judgment
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

Judgment Value

Malfunction Criteria

Threshold Value

Battery voltage

≥ 10.9 V

Ignition

Terminal output voltage when ECM outputs OFF signal LOW

Judgment Value

Malfunction Criteria

Threshold Value

Battery voltage

≥ 10.9 V

Ignition

Terminal output voltage when ECM outputs OFF signal HIGH

GD(H4DOTC)-149

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

CK: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 Judgment
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

than the predetermined time.

Time Needed for Diagnosis: Less than 1 second

CL: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)-148, DTC P0413 SECONDARY AIR

INJECTION SYSTEM SWITCHING VALVE “A” CIRCUIT OPEN, Diagnostic Trouble Code (DTC) Detecting

Criteria.>

CM: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)-149, DTC P0414 SECONDARY AIR

INJECTION SYSTEM SWITCHING VALVE “A” CIRCUIT SHORTED, Diagnostic Trouble Code (DTC) De-

tecting Criteria.>

Secondary Parameters

Enable Conditions

None

Judgment Value

Malfunction Criteria

Threshold Value

Battery voltage

≥ 10.9 V

Ignition

Terminal output voltage when ECM outputs ON signal

HIGH

Judgment Value

Malfunction Criteria

Threshold Value

Battery voltage

≥ 10.9 V

Ignition

Terminal output voltage when ECM outputs ON signal

LOW

GD(H4DOTC)-150

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

CN: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

(B)

Deterioration

(C)

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

(D)

Output waveform from the front
oxygen sensor

(1)

Front oxygen (A/F) sensor

(2)

Front oxygen sensor

(3)

Catalytic converter

EN-01713

(A)

(B)

(C)

(D)

(1)

(2)

(3)

GD(H4DOTC)-151

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

3. ENABLE CONDITIONS

4. GENERAL DRIVING CYCLE

Perform the diagnosis only once at a constant speed of 40 km/h (24.9 MPH) or higher.

5. DIAGNOSTIC METHOD

After the enable conditions have been established, calculate the front oxygen (A/F) sensor lambda value

deviation sum value (Σ |(sglmd

– sglmd

n–1

)|), and rear oxygen sensor output voltage deviation sum value

(Σ |(ro2sad

– ro2sad

n–1

)|) in every 32 ms × 4 times. If the front oxygen (A/F) sensor lambda value deviation

sum value (Σ |(sglmd

– sglmd

n–1

)|) is the predetermined value or more, calculate the diagnostic value.

• Abnormality Judgment
If the duration of time while the following conditions are met is within the time indicated, judge as NG.

Time Needed for Diagnosis: 30 — 55 seconds

Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-

cles.
• Normality Judgment
Judge as OK and clear the NG if the continuous time while the following conditions are established is within

the predetermined time.

Time Needed for Diagnosis: 30 — 55 seconds

Secondary Parameters

Enable Conditions

Battery voltage

≥ 10.9 V

Atmospheric pressure

≥ 75 kPa (563 mmHg, 22.2 inHg)

Engine coolant temperature

≥ –50 °C (–58 °F)

Estimated catalyst temperature

≥ 490 °C (914 °F)

Misfire detection every 200 rotations

< 65535 time(s)

Learning value of evaporation gas density

< 1

Sub feedback

In operation

Evaporative system diagnosis

Not in operation

Time of difference (< 0.10) between actual lambda and target lambda ≥ 0 ms
Vehicle speed

> 40 km/h (24.9 MPH)

Amount of intake air

≥ 10 g/s (0.35 oz/s)
and
< 50 g/s (1.76 oz/s)

Engine load change every 0.5 engine revs.

< 255 g/rev (8.99 oz/rev)

Rear oxygen output change from 660 mV or less to 660 mV or more

Experienced after fuel cut

Purge execution calculated time

≥ 0 s

Judgment Value

Malfunction Criteria

Threshold Value

Σ |(ro2sad

– ro2sad

n–1

)| / Σ |(sglmd

– sglmd

n–1

> 7.94 (Models without SI-DRIVE)
> 8 (Models with SI-DRIVE)

Judgment Value

Malfunction Criteria

Threshold Value

Σ |(ro2sad

– ro2sad

n–1

)| / Σ |(sglmd

– sglmd

n–1

≤ 7.94 (Models without SI-DRIVE)

≤ 8 (Models with SI-DRIVE)

Content .. 347 348 349 350 ..