2009 SUBARU TRIBECA fuel

GD(H6DO)-77
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2) Judge as NG when the oxygen sensor voltage at recovery from a deceleration fuel cut, is large.
If the fuel cut time in a deceleration fuel cut is long (more than 6 s), and even after recovering from a decel-
eration fuel cut, the oxygen sensor voltage is high (0.55 V or more), judge as NG.
Time Needed for Diagnosis: 1 time
Malfunction Indicator Light Illumination: Illuminates when malfunctions occur in 2 continuous driving cy-
cles.
Normality Judgment
1) Regardless of a deceleration fuel cut, if the response time (diagnosis value) when the oxygen sensor volt-
age has changed from rich to lean is shorter than the threshold value (judgment value), judge as a normal
condition.
Response time (diagnosis value) ≤ threshold value → normal
2) Do not judge as a normal condition.
Judge as OK when the criteria below are met.
6. DTC CLEAR CONDITION
•When the OK idling cycle is completed 40 times in a row
•When “Clear Memory” is performed
7. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
•When the OK driving cycle is completed 3 times in a row
•When “Clear Memory” is performed
8. FAIL SAFE
Sub feedback control: Not allowed
9. ECM OPERATION AT DTC SETTING
•Memorize the freeze frame data. (For test mode $02)
•Memorize the diagnostic value and trouble standard value. (For test mode $06)
10.ENABLE CONDITIONS
•Lean → rich response diagnosis
11.GENERAL DRIVING CYCLE
Perform the diagnosis only once when deceleration fuel cut occurs after rapid acceleration. (Pay attention to
the oxygen sensor voltage for the timing of the deceleration.)
Judgment Value
Malfunction Criteria Threshold Value
Shortest time change from rich (500 mV
O2 output) to lean (300 mV) if voltage
reduces from 550 mV to 250 mV.
> 0.327 sec.
or
Longest time over 550 mV > 2 sec.
Judgment Value
Malfunction Criteria Threshold Value
Shortest time change from rich (500 mV
O2 output) to lean (300 mV) if voltage
reduces from 550 mV to 250 mV.
≤ 0.327 sec.
Secondary Parameters Enable Conditions
Battery voltage > 10.9 V
A/F main feedback control condition Complete
5 seconds or more deceleration fuel cut. Experienced
After fuel cut≥ 2 sec.

GD(H6DO)-78
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
12.DIAGNOSTIC METHOD
Calculate the minimum value of 0.3 V to 0.5 V output ch a n g e r e s p on s e t im e a s ju d g m e n t v a lu e w h en th e re a r
oxygen sensor output voltage changes from 0.25 V (lean) to 0.55 V (rich).
Abnormality Judgment
1) Judge as NG when the judgment value is larger than the threshold value after deceleration fuel cut.
Response time (diagnosis value) > threshold value → abnormal
2) If the oxygen sensor voltage is small after recovering from a deceleration fuel cut, and remains small,
judge as NG.
Judgment Value
Malfunction Criteria Threshold Value
Shortest time change from lean (300 mV
O2 output) to rich (500 mV) when the
voltage drops from 500 mV to 250 mV.
> 2 sec.
or
Longest time under 250 mV > 120 sec.
EN-02210
Fuel cut on deceleration
Execute the malfunction judgement in 2 seconds
from recovery of fuel cut on deceleration.
Rear O2 sensor (V)
0V
>= 6s
>= 120s
0.25V
0.3V
0.5V
0.55V
Measure the response time
(diagnostic value).
Diagnosis execution
condition
Judge NG when the voltage of
rear oxgen sensor is 0.25 V or
less for 120 seconds or more
after recovery of fuel cut on
deceleration.

GD(H6DO)-79
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Time Needed for Diagnosis: 1 time
Malfunction Indicator Light Illumination: Illuminates when malfunctions occur in 2 continuous driving cy-
cles.
Normality Judgment
1) Regardless of a deceleration fuel cut, if the response time (diagnosis value) when the oxygen sensor volt-
age has changed from rich to lean is shorter than the threshold value (judgment value), judge as a normal
condition.
Response time (diagnosis value) ≤ threshold value → normal
2) Do not judge as a normal condition.
Judge as OK when the criteria below are met.
13.DTC CLEAR CONDITION
•When the OK idling cycle is completed 40 times in a row
•When “Clear Memory” is performed
14.MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
•When the OK driving cycle is completed 3 times in a row
•When “Clear Memory” is performed
15.FAIL SAFE
Sub feedback control: Not allowed
16.ECM OPERATION AT DTC SETTING
•Memorize the freeze frame data. (For test mode $02)
•Memorize the diagnostic value and trouble standard value. (For test mode $06)
Judgment Value
Malfunction Criteria Threshold Value
Shortest time change from lean (300 mV
O2 output) to rich (500 mV) when volt-
age drops from 550 mV to 250 mV.
≤ 2 sec.

GD(H6DO)-80
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AR:DTC P0140 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SEN-
SOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the rear oxygen sensor open or short circuit. Judge as NG when the rear oxygen sensor voltage can
be determined to be abnormal considering conditions such as intake air amount, engine coolant tempera-
ture, main feedback control and deceleration fuel cut.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITION (USED ONLY FOR MALFUNCTION JUDGMENT)
4. GENERAL DRIVING CYCLE
Perform the diagnosis once after starting the engine.
(A) Electromotive force (C) Rich (E) Theoretical air fuel ratio
(B) Air fuel ratio (D) Lean (F) Comparative voltage

(1) Atmosphere (2) Exhaust gas (3) Electromotive force
Secondary Parameters Enable Conditions
Closed loop control at the rear oxygen
sensor
In operation
Ta r g e t o u t p u t v o l t a g e o f t h e r e a r o x y g e n
sensor
≥ 0.6 V
Amount of intake air≥ 10 g/second
Engine coolant temperature≥ 75°C (167°F)
Misfire detection every 200 rotations≤ 7 times
Compensation factor for front oxygen (A/
F) sensor with main feedback control
Not in limit value
Battery voltage with main feedback con-
trol
> 10.9 V
Deceleration fuel cut of 5 seconds or
more.
Experienced
EN-01696
(3)V(1)
(2) (2)
(E)
(F)
(C) (B) (D)
(A)

GD(H6DO)-83
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BA:DTC P0171 SYSTEM TOO LEAN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect fuel system malfunction by the amount of main feedback control.
Diagnostic method
Fuel system is diagnosed by comparing the target air fuel ratio calculated by ECM with the actual air fuel ra-
tio measured by sensor.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously at idling or at a constant speed after warming up the engine.
4. DIAGNOSTIC METHOD
Abnormality Judgment
Compare the diagnosed value (fsobd) with the threshold value, and if a condition where the malfunction cri-
teria below are met continues for more than 50 seconds, judge that there is a fault in the fuel system.
Time Needed for Diagnosis: 10 seconds × 5 times
Malfunction Indicator Light Illumination: Illuminates when malfunctions occur in 2 continuous driving cy-
cles.
Normality Judgment
Judge as OK when the malfunction criteria below are completed for 10 seconds or more.
Secondary Parameters Enable Conditions
A/F main learning system In operation
Engine coolant temperature≥ 75°C (167°F)
Engine load≤ 0.02 g/rev
Intake air flow≥ Map 5
Map 5
Engine RPM (rpm) idle 700 1000 1500 2000 2500 3000 3500 4000 4500 5000
Measured value (g(oz)/rev) NA0.357
(0.013)
0.25
(0.009)
0.25
(0.009)
0.317
(0.011)
0.326
(0.011)
0.337
(0.012)
0.397
(0.014)
0.439
(0.015)
0.454
(0.016)
0.454
(0.016)
Judgment Value
Malfunction Criteria Threshold Value
fsobd = (sglmd – tglmda) + faf + flaf≥ fsobdL1
In this case: sglmd = measured lambda,
tglmda = target lambda, faf = main feed-
back compensation coefficient (every 64
milliseconds), flaf = main feedback learn-
ing compensation coefficient
Refer to Map 4.
fsobdL1 = lean side
threshold value of
fsobd
Map 4 Threshold value for fuel system malfunction criteria
Amount of air (g(oz)/s) 0 (0)3.2
(0.113)
6.4
(0.226)
9.6
(0.339)
12.8
(0.451)
16
(0.564)
19.2
(0.677)
fsobdL1 (%) 40 40 33.2 26.5 26.5 26.5 26.5
Judgment Value
Malfunction Criteria Threshold Value
fsobd = (sglmd – tglmda) + faf + flaf < 19%

GD(H6DO)-85
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BB:DTC P0172 SYSTEM TOO RICH (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect fuel system malfunction by the amount of main feedback control.
Diagnostic method
Fuel system is diagnosed by comparing the target air fuel ratio calculated by ECM with the actual air fuel ra-
tio measured by sensor.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously at idling or at a constant speed after warming up the engine.
4. DIAGNOSTIC METHOD
Abnormality Judgment
Compare the diagnosed value (fsobd) with the threshold value, and if a condition where the malfunction cri-
teria are met continues for more than 50 seconds, judge that there is a fault in the fuel system.
Time Needed for Diagnosis: 10 seconds × 5 times
Malfunction Indicator Light Illumination: Illuminates when malfunctions occur in 2 continuous driving cy-
cles.
Normality Judgment
Judge as OK when the malfunction criteria below continues for 10 seconds.
5. DTC CLEAR CONDITION
•When the OK idling cycle is completed 40 times in a row
•When “Clear Memory” is performed
Secondary Parameters Enable Conditions
A/F main learning system In operation
Engine coolant temperature≥ 75°C (167°F)
Cumulative time of canister purge after
engine start
20 seconds or more
Continuous period after canister purge
starting
30 seconds or more
Intake manifold absolute pressure≥ Map 1
Judgment Value
Malfunction Criteria Threshold Value
fsobd = (sglmd – tglmda) + faf + flaf≤ fsobdR1
In this case: sglmd = measured lambda,
tglmda = target lambda, faf = main feed-
back compensation coefficient (every 64
milliseconds), flaf = main feedback learn-
ing compensation coefficient
Refer to Map 4.
fsobdR1 = rich side
threshold value of
fsobd
Map 4
Amount of air (g(oz)/s) 0 (0)3.2
(0.113)
6.4
(0.226)
9.6
(0.339)
12.8
(0.451)
16
(0.564)
19.2
(0.677)
fsobdR1 (%) –40 –40 –31.2 –26.5 –26.5 –26.5 26.5
Judgment Value
Malfunction Criteria Threshold Value
fsobd = (sglmd – tglmda) + faf + flaf≥ –20%

GD(H6DO)-87
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BE:DTC P0181 FUEL TEMPERATURE SENSOR “A” CIRCUIT RANGE/PERFOR-
MANCE
1. OUTLINE OF DIAGNOSIS
Detect faults in the fuel temperature sensor output properties.
Diagnosis is performed in two methods; drift diagnosis and stuck diagnosis. If either is NG, judge as NG. If
both are OK, Judge as OK and clear the NG.
Drift Diagnosis
Normally fuel temperature is lower than engine coolant temperature. When the fuel temperature becomes
higher than the engine coolant temperature, the range is considered to be shifted, and judged as NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(A) Resistance value (Ω)(B)Fuel temperature °C (°F)
Secondary Parameters Enable Conditions
None
EN-01700
(A)
(B)

GD(H6DO)-88
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Abnormality Judgment
Judge as NG when the continuous time until completing the malfunction criteria below becomes 120 second
or more.
Time Needed for Diagnosis: 120 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunctions occur in 2 continuous driving cy-
cles.
Normality Judgment
Judge as OK when the criteria below are met.
Stuck Diagnosis
As the engine warms up (cumulative amount of intake air after starting is large), if the fuel temperature which
should rise does not, determine as being stuck and NG.
6. ENABLE CONDITIONS
7. GENERAL DRIVING CYCLE
Always perform diagnosis continuously.
Judgment Value
Malfunction Criteria Threshold Value
Fuel level≥ 9.6 2 (25.4 US gal,
2.11 Imp gal)
After engine starting 20 seconds or more
Engine coolant temperature - engine
coolant temperature at engine starting
> 10°C (50°F)
Fuel temperature – Engine coolant tem-
perature
≥ 10°C (50°F)
Battery voltage > 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Fuel level≥ 9.6 2 (25.4 US gal,
2.11 Imp gal)
After engine starting 20 seconds or more
Engine coolant temperature - engine
coolant temperature at engine starting
> 10°C (50°F)
Fuel temperature – Engine coolant tem-
perature
< 10°C (50°F)
Battery voltage > 10.9 V
Engine coolant temperature < 75°C (167°F)
Secondary Parameters Enable Conditions
After engine starting 20 seconds or more
Battery voltage > 10.9 V