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Home >> Lexus >> 2009 >> GX 470 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control (SFI) System (Diagnostic Codes (P0010-P0505)) >> 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

The monitor will run whenever these DTCs are not present P0010, P0020 (VVT Oil Control Valve)
P0011, P0021 (VVT System - Advance)
P0012, P0022 (VVT System - Retard)
P0016, P0018 (VVT System - Misalignment)
P0031, P0032, P0051, P0052 (Air Fuel Ratio Sensor Heater)
P0037, P0038, P0057, P0058 (Rear Oxygen Sensor Heater)
P2195, P2196, P2197, P2198, P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2255, P2256, P2A00, P2A03 (Air Fuel Ratio Sensor)
P0136, P0137, P0138, P0156, P0157, P0158, P0606 (Rear Oxygen Sensor)
P0100, P0102, P0103 (Mass Air Flow Sensor)
P0115, P0117, P0118 (Engine Coolant Temperature Sensor)
P0125 (Insufficient Coolant Temperature for Closed Loop Fuel Control)
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135 (Throttle Position Sensor)
P0171, P0172, P0174, P0175 (Fuel System)
P0300 - P0308 (Misfire)
P0335 (Crankshaft Position Sensor)
P1340 (Camshaft Position Sensor)
P0340, P0345 (VVT Sensor)
P0351 - P0358 (Igniter)
P0412, P0418, P1613 (Secondary Air Injection System Control)
P1441, P1442, P1444, P1445, P2440, P2441, P2444, P2445 (Secondary Air Injection System)
P0500 (Vehicle Speed Sensor)
Battery voltage 11 V or more
Intake air temperature -10°C (14°F) or more
Engine coolant temperature 75°C (167°F) or more
Atmospheric pressure coefficient 76 kPa (525 mmHg) or more
Idle OFF
Engine RPM Less than 3200 RPM
A/F sensor Activated
Fuel system status Closed-loop
Engine load 10 to 70 %
All of the following conditions are met Conditions 1, 2 and 3
1. MAF 6 to 75 g/sec. (Varies with engine RPM)
2. Front catalyst temperature (estimated) 715 to 830°C (1319 to 1526°F)
3. Rear catalyst temperature (estimated) 410 to 830°C (770 to 1526°F)
EVAP system monitor The monitor has not run yet or the vacuum introduction has been completed
A/F sensor monitor Completed
Rear HO2S heater monitor Completed
Shift position 4th or more