LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Subaru >> 2012 >> Forester XT Premium >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DO) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0420 Catalyst System Efficiency Below Threshold (Bank 1) >> Enable Condition
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Enable Condition

ENABLE CONDITION REFERENCE CHART

Secondary Parameters Enable Conditions
Battery voltage ≥ 10.9 V
Atmospheric pressure ≥ 75 kPa (563 mmHg, 22.2 inHg)
Engine coolant temperature ≥ 70°C (158°F)
Estimated catalyst temperature ≥ 580°C (1076 °F) (AT model)
  ≥ 580°C (1076 °F) (MT model)
Misfire detection every 200 rotations < 5 time(s)
Learning value of evaporation gas density < 0.2
Sub feedback In operation
Evaporative system diagnosis Not in operation
Time of difference (< 0.10) between actual lambda and target lambda ≥ 1000 ms
Vehicle speed > 60 km/h (37.3 MPH)
Amount of intake air ≥ 10g/s (0.35oz/s)
  and
  < 35g/s (1.23 oz/s)
Engine load change every 0.5 engine revs. < 0.02 g/rev (0 oz/rev)
Rear oxygen output change from 660 mV or less to 660 mV or more Experienced after fuel cut
Elapsed time after starting the engine ≥ 230 second
Purge execution calculated time ≥ 0s