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Home >> Subaru >> 2005 >> Forester XT, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0420 Catalyst System Efficiency Below Threshold (Bank 1) >> Enable Condition
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Enable Condition

ENABLE CONDITION

Secondary Parameters Enable Conditions
Time for keep completing all secondary parameters 1.2 seconds or more
Battery voltage > 10.9 V
Atmospheric pressure > 75.0 kPa (563 mmHg, 22.2 inHg)
Engine coolant temperature >/= 70°C (158°F)
Catalyst warm-up counter on Map 2 >/= 7600
Misfire detection during 200 engine revs. < 5 times
Learning value of evaporation gas density < 0.20
Sub feedback Operating
Evaporative system diagnostic Not in operation
Difference between actual and target time lambda < 0.10 1000 milliseconds or more
Vehicle speed >/= 75 km/h (47 MPH)
Amount of intake air 10 <-- --> 40 g/s
Engine load change every 0.5 engine revs. < 0.03 g/rev
Rear O2 output change from lean 600 mV to rich. Experienced after fuel cut
After engine starting >/= 200 seconds
Engine speed 1600 - 3500 RPM
Accumulative time of canister purge after engine starting >/= 19.9 seconds

Add the following value every 512 milliseconds.

Catalyst warm-up counter </= 9000 

CATALYST WARM-UP COUNTER </= 9000

Amount of intake air (g/s) 0 5 7.5 10 15 20 25 30 35 40 45 50
Integrated value for warm-up counter -18 -5 3 11 25 40 57 72 87 100 100 100

Catalyst warm-up counter > 9000 

CATALYST WARM-UP COUNTER > 9000

Amount of intake air (g/s) 0 5 7.5 10 15 20 25 30 35 40 45 50
Integrated value for warm-up counter -8 -4 -1 3 6 8 9 11 13 14 14 14