obd SUBARU TRIBECA 2009 1.G Service User Guide

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%