Subaru Legacy IV (2008 year). Manual - part 609

GD(H6DO)-56

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

2. COMPONENT DESCRIPTION

3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE

Perform diagnosis only once at a constant speed of 10 km/h — 120 km/h (6.2 MPH — 74.6 MPH) 120000 ms
or more after starting the engine.

(A)

Electromotive force

(C)

Lean

(D)

Rich

(B)

Air fuel ratio

(1)

Atmosphere

(3)

ZrO

2

(4)

Ceramic heater

(2)

Exhaust gas

 

 

Secondary Parameters

Enable Conditions

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

t 1024 ms

Battery voltage

t 10.9 V

Barometric pressure

> 75 kPa (563 mmHg, 
22.2 inHg)

Closed loop control with main feedback

Operation

Front oxygen (A/F) sensor impedance

0 

: — 50 :

Elapsed time after starting the engine

t 120000 ms

Engine coolant temperature

t 75 °C (167 °F)

Engine speed

1000 rpm — 2500 rpm

Vehicle speed

10 km/h — 120 km/h 
(6.2 MPH — 74.6 MPH)

Amount of intake air

10 g/s — 40 g/s 
(0.35 oz/s — 1.41 oz/s)

Engine load

< 0.02 g/rev (0 oz/rev)

Learning value of EVAP conc. during 
purge

< 0.2 

Total time of operating canister purge

t 19.9 s

(1)

(2)

(4)

(2)

(3)

EN-01693

(C)

(B)

(D)

(A)

GD(H6DO)-57

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

5. DIAGNOSTIC METHOD

Calculate faf difference every 32ms × 4 , and the 

O value difference. Calculate the diagnosis value after cal-

culating 820 time(s).

• 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: 32 ms × 4  × 820 time(s)
Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cy-
cles.

• 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: 32 ms × 4  × 820 time(s)

Judgement Value

Malfunction Criteria

Threshold Value

parafca = td2faf/td2lmd

> 0.2 

where,

 

td2faf (N) = td2faf (n–1) + |d2faf (n)|

 

td2lmd (N) = td2lmd (n–1) + |d2lmd (n)|

 

add up to 32 ms × 4  × 820 time(s).

 

d2faf (n) = (faf (n) – faf (n–1)) – (faf (n–1) 
– faf (n–2))

d2lmd (n) = (lmd (n) – lmd (n–1)) – (lmd 
(n–1) – lmd (n–2))

faf = main feedback compensation coef-
ficient every 128 milliseconds

lmd = output lambda every 128 millisec-
onds

Judgement Value

Malfunction Criteria

Threshold Value

parafca = td2faf/td2lmd

d 0.2 

where,

 

td2faf (N) = td2faf (n–1) + |d2faf (n)|

 

td2lmd (N) = td2lmd (n–1) + |d2lmd (n)|

 

add up to 32 ms × 4  × 820 time(s).

 

d2faf (n) = (faf (n) – faf (n–1)) – (faf (n–1) 
– faf (n–2))

d2lmd (n) = (lmd (n) – lmd (n–1)) – (lmd 
(n–1) – lmd (n–2))

faf = main feedback compensation coef-
ficient every 128 milliseconds

lmd = output lambda every 128 millisec-
onds

GD(H6DO)-58

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

AN:DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED 

(BANK 1 SENSOR 1)

1. OUTLINE OF DIAGNOSIS

Detect open circuits of the sensor.
Judge as NG when the impedance of the element is large.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

(A)

Electromotive force

(C)

Lean

(D)

Rich

(B)

Air fuel ratio

(1)

Atmosphere

(3)

ZrO

2

(4)

Ceramic heater

(2)

Exhaust gas

 

 

Secondary Parameters

Enable Conditions

None

 

(1)

(2)

(4)

(2)

(3)

EN-01693

(C)

(B)

(D)

(A)

GD(H6DO)-59

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: 5000 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

Battery voltage

t 10.9 V

Time of heater control duty at 70 % or 
more

t 30000 ms

Front oxygen (A/F) sensor impedance.

> 500 

:

Judgement Value

Malfunction Criteria

Threshold Value

Battery voltage

t 10.9 V

Front oxygen (A/F) sensor impedance.

d 500 :