Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 330

GD(H4DOTC)-72

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: 5000 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

Battery voltage

≥ 10.9 V

Time of heater control duty at 70 % or more

≥ 36000 ms

Front oxygen (A/F) sensor impedance.

> 500 Ω

Judgment Value

Malfunction Criteria

Threshold Value

Battery voltage

≥ 10.9 V

Front oxygen (A/F) sensor impedance.

≤ 500 Ω

GD(H4DOTC)-73

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

AO:DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)

1. OUTLINE OF DIAGNOSIS

Detect continuity NG of the oxygen sensor. If the oxygen sensor voltage reading is not within the probable

range considering the operating conditions, judge as NG.

2. COMPONENT DESCRIPTION

(A)

Electromotive force

(B)

Air fuel ratio

(C)

Lean

(D)

Rich

(E)

Theoretical air fuel ratio

(F)

Comparative voltage

(1)

Atmosphere

(2)

Exhaust gas

(3)

Electromotive force

EN-01696

(3)

V

(1)

(2)

(2)

(E)

(F)

(C)

(B)

(D)

(A)

GD(H4DOTC)-74

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

3. ENABLE CONDITIONS

4. GENERAL DRIVING CYCLE

After starting the engine, continuously perform the diagnosis with the same engine condition.

Used for abnormality judgment

Secondary Parameters

Enable Conditions

High

Secondary air system

Not in operation

Closed loop control at the oxygen sensor

In operation

Misfire detection every 200 rotations

< 65535 time(s)

Front oxygen (A/F) sensor compensation coefficient

Not in limit value

Battery voltage

≥ 10.9 V

Engine coolant temperature

≥ 70 °C (158 °F)

Low (1)

Secondary air system

Not in operation

Closed loop control at the oxygen sensor

In operation

Misfire detection every 200 rotations

< 65535 time(s)

Front oxygen (A/F) sensor compensation coefficient

Not in limit value

Battery voltage

≥ 10.9 V

Engine coolant temperature

≥ 70 °C (158 °F)

Amount of intake air

≥ 10 g/s (0.35 oz/s)

Low (2)

Secondary air system

Not in operation

Closed loop control at the oxygen sensor

In operation

Misfire detection every 200 rotations

< 65535 time(s)

Front oxygen (A/F) sensor compensation coefficient

Not in limit value

Battery voltage

≥ 10.9 V

Engine coolant temperature

≥ 70 °C (158 °F)

Amount of intake air

< 10 g/s (0.35 oz/s)

Current continuation time of the rear oxygen sensor heater

≥ 25000 ms

Low (3)

Secondary air system

Not in operation

Closed loop control at the oxygen sensor

In operation

Misfire detection every 200 rotations

< 65535 time(s)

Front oxygen (A/F) sensor compensation coefficient

Not in limit value

Battery voltage

≥ 10.9 V

Engine coolant temperature

≥ 70 °C (158 °F)

Amount of intake air

< 10 g/s (0.35 oz/s)

Current continuation time of the rear oxygen sensor heater

≥ 25000 ms

Fuel cut

Experienced

Used for normality judgment

Secondary Parameters

Enable Conditions

Secondary air system

Not in operation

Closed loop control at the oxygen sensor

In operation

Misfire detection every 200 rotations

< 65535 time(s)

Front oxygen (A/F) sensor compensation coefficient

Not in limit value

Battery voltage

≥ 10.9 V

Engine coolant temperature

≥ 70 °C (158 °F)

GD(H4DOTC)-75

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:

High: 2500 ms

Low (1): 20000 ms

Low (2): 150000 ms

Low (3): Value from Map

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 more

than the predetermined time.

Time Needed for Diagnosis:

High: Less than 1 second

Low (1): Less than 1 second

Low (2): Less than 1 second

Low (3): Less than 1 second

AP:DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)

1. OUTLINE OF DIAGNOSIS

NOTE:

For the detection standard, refer to DTC P0137. <Ref. to GD(H4DOTC)-73, DTC P0137 O2 SENSOR CIR-

CUIT LOW VOLTAGE (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

Judgment Value

Malfunction Criteria

Threshold Value

DTC

High

P0138

Sensor output voltage

> 1.2 V

Low

P0137

Sensor output voltage

< 0.03 V

Map

Fuel cut time (s)

0

2000

10000

Time Needed for Diagnosis (s)

150000

150000

150000

Judgment Value

Malfunction Criteria

Threshold Value

DTC

High

P0138

Sensor output voltage

≤ 1.2 V

Low

P0137

Sensor output voltage

≥ 0.03 V