Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 321

GD(H4DOTC)-36

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

X: DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT

1. OUTLINE OF DIAGNOSIS

Detect open or short circuits of the air flow sensor.

Judge as NG if out of specification.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITIONS

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

(A)

Air

(1)

Air flow sensor

(3)

Voltage (V)

(4)

Amount of intake air (kg (lb)/s)

(2)

Intake air temperature sensor

Secondary Parameters

Enable Conditions

None

EN-01766

(3)

(4)

(2)

(1)

(A)

GD(H4DOTC)-37

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

5. 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: 500 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

Judgment Value

Malfunction Criteria

Threshold Value

Output voltage

≤ 0.22 V

Judgment Value

Malfunction Criteria

Threshold Value

Output voltage

> 0.22 V

GD(H4DOTC)-38

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

Y: DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT

1. OUTLINE OF DIAGNOSIS

Detect open or short circuits of the air flow sensor.

Judge as NG if out of specification.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITIONS

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

(A)

Air

(1)

Air flow sensor

(3)

Voltage (V)

(4)

Amount of intake air (kg (lb)/s)

(2)

Intake air temperature sensor

Secondary Parameters

Enable Conditions

None

EN-01766

(3)

(4)

(2)

(1)

(A)

GD(H4DOTC)-39

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

5. 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: 500 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

Judgment Value

Malfunction Criteria

Threshold Value

Output voltage

≥ 4.952 V

Judgment Value

Malfunction Criteria

Threshold Value

Output voltage

< 4.952 V