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Home >> Lexus >> 2025 >> NX 350h >> Repair and Diagnosis >> External Pages >> Different car >> Section 103 (Engine Control System - Diagnostic Codes (P0300-P0460)) >> SFI System >> DTC P0420-00: Catalyst System Efficiency Below Threshold Bank 1 [11/2021 - 03/2023] >> Monitor Strategy

Monitor Strategy

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Related DTCs P0420: Catalyst deterioration
Required Sensors/Components (Main) Air fuel ratio sensor (sensor 1)
Air fuel ratio sensor (sensor 2)
Required Sensors/Components (Related) Intake air temperature sensor
Mass air flow meter sub-assembly
Crankshaft position sensor
Engine coolant temperature sensor
Frequency of Operation Once per driving cycle
Duration Approximately 30 seconds
MIL Operation Immediate
Sequence of Operation None