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Home >> Toyota >> 2005 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control System (SFI) (1ZZ-FE (Fwd)) - Diagnostics >> SFI System (1ZZ-FE (Ff)) >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) >> Typical Enabling Conditions
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Typical Enabling Conditions

TYPICAL ENABLING CONDITIONS (DTC P0420)

Monitor runs whenever following DTCs not present See LIST OF DISABLE A MONITOR 
Battery voltage 11V or more
Engine coolant temperature sensor 75°C (167°F) or more
Idling OFF
Engine RPM Less than 4,000 RPM
A/F sensor status Activated
Sub feedback control Executed
Fuel cut OFF (for 5 seconds or more)
Engine load 10 to 80%
Mass air flow rate 2.5 to 33 g/second
Estimated catalyst temperature Front catalyst: 620° to 830°C (1,148° to 1,526°F) (M/T) 620° to 840°C (1,148° to 1,544°F) (A/T) Rear catalyst: 400° to 760°C (752° to 1,400°F)
Fuel trim deviation Within +/-5%
Shift position D (A/T), or 4th or 5th gear (M/T)