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Home >> Lexus >> 2009 >> IS 250 RWD, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS P0420 - U0101 & Circuit Tests) >> SFI System >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1); DTC P0430: Catalyst System Efficiency Below Threshold (Bank 2) >> Typical Enabling Conditions
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Typical Enabling Conditions

Monitor runs whenever following DTCs are not present P0010, P0020 (OCV bank 1, 2)
P0011, P0021 (VVT system bank 1, 2 - advance)
P0012, P0022 (VVT system bank 1, 2 - retard)
P0013, P0023 (Exhaust OCV bank 1, 2)
P0014, P0024 (Exhaust VVT system bank 1, 2 - advance)
P0015, P0025 (Exhaust VVT system bank 1, 2 - retard)
P0016, P0018 (VVT system bank 1, 2 - misalignment)
P0017, P0019 (Exhaust VVT system bank 1, 2 - misalignment)
P0031, P0032, P0051, P0052 (A/F sensor heater)
P0037, P0038, P0057, P0058 (HO2 sensor heater)
P0100, P0102, P0103 (MAF meter)
P0115, P0117, P0118 (ECT sensor)
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135 (TP sensor)
P0125 (Insufficient ECT for closed loop)
P0136, P0137, P0138, P0139 (HO2 sensor bank 1)
P0156, P0157, P0158, P0159 (HO2 sensor bank 2)
P0171, P0172, P0174, P0175 (Fuel system)
P0301, P0302, P0303, P0304, P0305, P0306 (Misfire)
P0335 (CKP sensor)
P0340, P0342, P0343, P0345, P0347, P0348 (VVT sensor)
P0351, P0352, P0353, P0354, P0355, P0356 (Igniter)
P0365, P0367, P0368, P0390, P0392, P0393 (Exhaust VVT sensor)
P0500 (Vehicle speed sensor)
P0606 (HO2 sensor - sensor 2)
P2195, P2196, P2197, P2198 (A/F sensor - rationality)
P2237, P2240 (A/F sensor - open)
P2238, P2241, P2252, P2255 (A/F sensor - low impedance)
P2239, P2242, P2253, P2256 (A/F sensor - high impedance)
P2A00, P2A03 (A/F sensor - slow response)
Battery voltage 11 V or more
IAT -10°C (14°F) or more
Engine coolant temperature 75°C (167°F) or more
Atmospheric pressure 76 kPa (570 mmHg) or more
Idle OFF
Engine RPM Less than 4000 RPM
A/F sensor Activated
Fuel system status Closed loop
Engine load 10 to 75%
All of the following conditions are met: Condition 1, 2 and 3
1. MAF 5 to 45 g/sec.
2. Front catalyst temperature (estimated) 600 to 840°C (1112 to 1544°F)
3. Rear catalyst temperature (estimated) 600 to 840°C (1112 to 1544°F)
Rear HO2S monitor Completed
Shift position 4th or higher