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Subaru Legacy IV (2008 year). Manual - part 194

GD(H4SO)-78

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

AS:DTC P0223 THROTTLE/PEDAL POSITION SENSOR/SWITCH “B” CIRCUIT

HIGH

1. OUTLINE OF DIAGNOSIS

Detect the open or short circuit of throttle position sensor 2.
Judge as NG if out of specification.

2. COMPONENT DESCRIPTION

3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

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: 24 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: 24 ms

(1)

Throttle position sensor 1 signal

(3)

Throttle position sensor

(4)

Engine control module (ECM)

(2)

Throttle position sensor 2 signal

Secondary Parameters

Enable Conditions

Ignition switch

Battery voltage

t 6 V

Judgement Value

Malfunction Criteria

Threshold Value

Sensor 2 input voltage

t 4.858 V

Judgement Value

Malfunction Criteria

Threshold Value

Sensor 2 input voltage

< 4.858 V

EN-01859

(1)

(2)

(3)

(4)

GD(H4SO)-79

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

AT:DTC P0301 CYLINDER 1 MISFIRE DETECTED

1. OUTLINE OF DIAGNOSIS

Detect the presence of misfire occurrence. (Revolution fluctuation method)
Monitoring Misfire which influences exhaust deterioration (1.5 times of FTP) and catalyst damage is made
obligatory by the law. Misfire affecting these two has two patterns below. :
• Intermittent misfire (The same cylinder misfires in random, or different cylinders misfire in random.) : FTP
1.5 times misfire
• Every time misfire (The same cylinder misfires every time.) : FTP 1.5 times misfire, Catalyst damage mis-
fire
The following detecting methods are adopted for these detection.
1) Intermittent misfire: FTP 1.5 times misfire
• 180° Interval Difference Method (MT: 1,800 rpm or less; AT: None)
• 360° Interval Difference Method (whole range)
• 720° Interval Difference Method (3,000 rpm or more)
2) Misfire every time: FTP 1.5 times misfire, Catalyst damage misfire
• 360° Interval Difference Method

2. ENABLE CONDITION

Secondary Parameters

Enable Conditions

All secondary parameters enable condi-
tions

t 1024 ms

Intake manifold pressure change at
180°CA

< Value of Map 1

Throttle position change during 16 milli-
seconds

< 21 °

Fuel shut-off function

Not in operation

Fuel level

t 9.6

2 (2.54 US gal,

2.11 Imp gal)

Vehicle dynamic control or AT torque
control

Not in operation

Evaporative system leak check

Not in operation

Engine speed

460 rpm — 6300 rpm

Intake manifold pressure

t Value from Map 2

Battery voltage

t 8 V

Fuel parameter determination

Not extremely low vol-
atility

Elapsed time after starting the engine

t 0 ms

Engine load change during 32 millisec-
onds

< 1000 rpm

GD(H4SO)-80

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

Map1
• AT model

• MT model

Map2
• AT model

• MT model

3. GENERAL DRIVING CYCLE

• If conditions are met, it is possible to detect the misfires from idling to high engine speed. However, to
avoid excessive load or harm to the engine, perform diagnosis at idle.
• Perform the diagnosis continuously.

rpm

700

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6300

kPa
(mmHg,
inHg)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

rpm

650

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6300

kPa
(mmHg,
inHg)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

13.3

(100,

3.9)

rpm

700

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6300

kPa
(mmHg,
inHg)

(195.0,

7.7)

23.9

(179.5,

7.1)

23.3

(174.7,

6.9)

23.1

(173.2,

6.8)

23.6

(176.8,

25.1

(188.0,

7.4)

26.2

(196.9,

7.8)

26.6

(199.6,

7.9)

26.9

(201.5,

7.9)

(225.0,

8.9)

33.4

(250.4,

9.9)

37.8

(283.5,

11.2)

39.5

(296.0,

11.7)

Vehicle speed < 64 km/h (39.8 MPH)

rpm

650

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6300

kPa
(mmHg,
inHg)

24.5

(184,

7.2)

22.7

(170.3,

6.7)

21.4

(160.2,

6.3)

21.5

(161.6,

6.4)

21.5

(161.4,

6.4)

23.2

(174.4,

6.9)

24.7

(185.5,

7.3)

25.8

(193.3,

7.6)

27.1

(203.2,

28.8

(216.3,

8.5)

32.3

(242.2,

9.5)

36.3

(272,
10.7)

37.9

(284.5,

11.2)

Vehicle speed

t 68 km/h (42.3 MPH)

rpm

650

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6300

kPa
(mmHg,
inHg)

31.6

(237,

9.3)

31.6

(237,

9.3)

31.6

(237,

9.3)

31.1

(233,

9.2)

31.3

(235,

9.3)

33.1

(248,

9.8)

33.9

(254,

10)

28.8

(216,

8.5)

30.1

(226,

8.9)

33.3

(250,

9.8)

36.9

(277,
10.9)

40.1

(301,
11.9)

43.2

(324,
12.8)

GD(H4SO)-81

Diagnostic Trouble Code (DTC) Detecting Criteria

GENERAL DESCRIPTION

4. DIAGNOSTIC METHOD

When a misfire occurs, the engine speed will decreased and the crankshaft position speed will change. Cal-
culate the interval difference value (diagnostic value) from crankshaft position speed by the following formu-
la, and judge whether a misfire is occurring or not comparing the calculated result with judgment value.
Counting the number of misfires. If the misfire ratio is higher during 1000 revs. or 200 revs., Judge corre-
sponding cylinders as NG.

As shown in the following figure, pick a cylinder as the standard and name it omg 0. And the former crank-
shaft position speed is named omg 1, the second former crankshaft position speed is named omg 2, the third
is named omg 3, etc.

Diagnostic value calculation
(Calculate from angle speed)

Misfire detection every single ignition
(Compare diagnostic value with judg-
ment value)

NG judgment (Misfire occurrence judg-
ment required by the law) (Compare
number of misfire with judgment)

• 180° Interval Difference Method
• 360° Interval Difference Method
• 720° Interval Difference Method

• FTP 1.5 times misfire NG judgment
• Catalyst damage misfire NG judgment

(A)

Ignition order

(B)

Crankshaft position speed

EN-01774

(A)

(B)

omg0

omg1

omg2

omg3

omg4

omg5

omg6

omg7

Content .. 192 193 194 195 ..