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Home >> Toyota >> 2005 >> Prius >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (SFI) - Diagnostics >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) >> Typical Enabling Conditions
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Typical Enabling Conditions

TYPICAL ENABLING CONDITIONS

The monitor will run whenever the following DTCs are not present See LIST OF DISABLE A MONITOR 
Battery voltage 11.5 V or more
Altitude Less than 2,400 m (8,000 ft)
Intake air temperature -10°C (14°F) or more
Idle OFF
Engine speed Less than 3,200 RPM
Engine coolant temperature 75°C (157°F) or more
Estimated catalyst temperature conditions are met: 1 & 2
1. Upstream estimated catalyst temperature Less than 800°C (1,508°F), and 430°F) or more
2. Downstream estimated catalyst temperature Less than 675°C (1,292°F), and 290°C (554°F) or more
Fuel system status Closed-loop