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Home >> Scion >> 2012 >> tC Standard Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0010-P0504)) >> SFI System >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) >> Typical Enabling Conditions
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Typical Enabling Conditions

Monitor runs whenever following DTCs not stored P0010 (VVT oil control valve)
P0011 (VVT system - Advance)
P0012 (VVT system - Retard)
P0013 (Exhaust VVT oil control valve)
P0014 (Exhaust VVT system - Advance)
P0015 (Exhaust VVT system - Retard)
P0016 (VVT system - Misalignment)
P0017 (Exhaust VVT system - Misalignment)
P0031, P0032, P101D (Air fuel ratio sensor heater)
P0037, P0038, P102D (Rear oxygen sensor heater)
P0102, P0103 (Mass air flow meter)
P0115, P0117, P0118 (Engine coolant temperature sensor)
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135 (Throttle position sensor)
P0125 (Insufficient coolant temperature for closed loop fuel control)
P0136, P0137, P0138, P0139, P0607 (Rear oxygen sensor)
P014C, P014D, P015A, P015B, P2195, P2196, P2237, P2238, P2239, P2252, P2253 (Air fuel ratio sensor)
P0171, P0172 (Fuel system)
P0301 - P0304 (Misfire)
P0335 (Crankshaft position sensor)
P0340 (Camshaft position sensor)
P0340, P0342, P0343 (VVT sensor)
P0351 - P0354 (Igniter)
P0365, P0367, P0368 (Exhaust VVT sensor)
P0500 (Vehicle speed sensor)
P219A (Air fuel ratio imbalance)
Battery voltage 11 V or higher
Intake air temperature -10°C (14°F) or higher
Engine coolant temperature 75°C (167°F) or higher
Atmospheric pressure 76 kPa (570 mmHg) or higher
Idling OFF
Engine speed Less than 4000 RPM
Air fuel ratio sensor status Activated
Fuel system status Closed loop
Engine load 10 to 80%
All of following conditions (a), (b) and (c) met -
(a) Mass air flow 2.5 to 60 gm/s
(b) Estimated front catalyst temperature 630 to 905°C (1166 to 1661°F) [AT]
600 to 850°C (1112 to 1562°F) [MT]
(c) Estimated rear catalyst temperature 390 to 770°C (734 to 1418°F) [AT]
370 to 770°C (698 to 1418°F) [MT]
Transmission gear 5th or higher [AT]
3rd or higher [MT]

HINT: 

The estimated catalyst temperature can be read in the Data List using the Techstream.