Note. For circuit reference, see WIRING DIAGRAMS article. For connector terminal identification, see CONNECTOR IDENTIFICATION .
Home/Oldsmobile/Bravada/Oldsmobile Bravada III (2001-2004)/Repair manual/Testing & Diagnostics/DTC P0420: TWC SYSTEM - LOW EFFICIENCY
Contents
Wiring diagrams Section: Testing & Diagnostics- Engine Control System - Self-Diagnostics - 4.2L: Overview
- Engine Control System - Self-Diagnostics - 4.2L: Diagnosis
- Engine Control System - Self-Diagnostics - 4.2L: Maintenance
- Engine Control System - Self-Diagnostics - 4.2L: Wiring
- Engine Control System - Self-Diagnostics - 4.2L: Component Locations
- Engine Control System - Self-Diagnostics - 4.2L: NVH
- Engine Control System - Self-Diagnostics - 4.2L: Other
- DTC P0013: CAMSHAFT POSITION ACTUATOR SOLENOID CIRCUIT
- DTC P0014: CAM PHASER PERFORMANCE
- DTC P0105: MAP SYSTEM PERFORMANCE
- DTC P0107: MAP SENSOR CIRCUIT - LOW VOLTAGE
- DTC P0108: MAP SENSOR CIRCUIT - HIGH VOLTAGE
- DTC P0112: IAT SENSOR CIRCUIT - LOW VOLTAGE
- DTC P0113: IAT SENSOR CIRCUIT - HIGH VOLTAGE
- DTC P0116: ECT SENSOR PERFORMANCE
- DTC P0117: ECT SENSOR CIRCUIT - LOW VOLTAGE
- DTC P0118: ECT SENSOR CIRCUIT - HIGH VOLTAGE
- DTC P0122: TP SENSOR CIRCUIT - LOW VOLTAGE
- DTC P0123: TP SENSOR CIRCUIT - HIGH VOLTAGE
- DTC P0125: EXCESSIVE TIME TO ENTER CLOSED LOOP FUEL CONTROL
- DTC P0128: ECT LESS THAN THERMOSTAT REGULATING TEMPERATURE
- DTC P0130: CLOSED LOOP RATIONALITY
- DTC P0131: HO2S CIRCUIT - LOW VOLTAGE - SENSOR 1
- DTC P0132: HO2S CIRCUIT - HIGH VOLTAGE - SENSOR 1
- DTC P0133: HO2S CIRCUIT - SLOW RESPONSE - SENSOR 1
- DTC P0134: HO2S CIRCUIT - INSUFFICIENT ACTIVITY - SENSOR 1
- DTC P0135 & P0141: HO2S HEATER CIRCUIT - SENSORS 1 & 2
- DTC P0137: HO2S CIRCUIT - LOW VOLTAGE - SENSOR 2
- DTC P0138: HO2S CIRCUIT - HIGH VOLTAGE - SENSOR 2
- DTC P0140: HO2S CIRCUIT - INSUFFICIENT ACTIVITY - SENSOR 2
- DTC P0171: FUEL TRIM SYSTEM LEAN
- DTC P0172: FUEL TRIM SYSTEM RICH
- DTC P0201-P0206: FUEL INJECTOR CONTROL CIRCUIT
- DTC P0300: ENGINE MISFIRE DETECTED
- DTC P0301-P0306: ENGINE MISFIRE DETECTED IN CYLINDER NO. 1-6
- DTC P0326: KNOCK SENSOR MODULE CIRCUIT
- DTC P0327 & P0332: KNOCK SENSOR CIRCUIT - LOW VOLTAGE
- DTC P0335: CRANKSHAFT POSITION SENSOR CIRCUIT
- DTC P0336: CRANKSHAFT POSITION SENSOR CIRCUIT PERFORMANCE
- DTC P0340: CAMSHAFT POSITION SENSOR
- DTC P0341: CAMSHAFT POSITION SENSOR CIRCUIT PERFORMANCE
- DTC P0420: TWC SYSTEM - LOW EFFICIENCY
- DTC P0440: EVAP SYSTEM - LARGE LEAK
- DTC P0442: EVAP SYSTEM - SMALL LEAK
- DTC P0446: EVAP VENT VALVE PERFORMANCE
- DTC P0452: FUEL TANK PRESSURE SENSOR - LOW VOLTAGE
- DTC P0453: FUEL TANK PRESSURE SENSOR - HIGH VOLTAGE
- DTC P0502: VEHICLE SPEED SENSOR LOW OUTPUT
- DTC P0503: VEHICLE SPEED SENSOR ERRATIC
- DTC P0506: IDLE CONTROL SYSTEM - LOW RPM
- DTC P0507: IDLE CONTROL SYSTEM - HIGH RPM
- DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 & P1683: PCM MEMORY
- DTC P0705: TRANSMISSION RANGE SWITCH
- DTC P0719: BRAKE SWITCH CIRCUIT - LOW INPUT
- DTC P0724: BRAKE SWITCH CIRCUIT - HIGH INPUT
- DTC P1120: TP SENSOR CIRCUIT
- DTC P1133: HO2S CIRCUIT - INSUFFICIENT SWITCHING - SENSOR 1
- DTC P1137: HO2S CIRCUIT - LOW VOLTAGE - SENSOR 2
- DTC P1138: HO2S CIRCUIT - HIGH VOLTAGE - SENSOR 2
- DTC P1171: LEAN EXHAUST UNDER HEAVY LOAD
- DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE
- DTC P1221: EXCESSIVE DIFFERENCE BETWEEN THROTTLE POSITION SENSORS
- DTC P1271: EXCESSIVE DIFFERENCE BETWEEN ACCELERATOR PEDAL POSITION SENSORS
- DTC P1275: ACCELERATOR PEDAL POSITION CIRCUIT - SENSOR 1
- DTC P1280: ACCELERATOR PEDAL POSITION CIRCUIT - SENSOR 2
- DTC P1336: CRANKSHAFT SYSTEM VARIATION NOT LEARNED
- DTC P1345: CRANKSHAFT/CAMSHAFT POSITION SENSOR CORRELATION
- DTC P1380: EBCM DTC DETECTED ROUGH ROAD DATA UNSTABLE
- DTC P1381: MISFIRE DETECTED - NO EBCM/PCM SERIAL DATA
- DTC P1441: EVAP SYSTEM FLOW DURING NON-PURGE
- DTC P1512: COMMAND VS. ACTUAL THROTTLE POSITION CORRELATION ERROR
- DTC P1514: AIRFLOW RATE EXCESSIVE
- DTC P1515: PREDICTED VS. ACTUAL THROTTLE POSITION CORRELATION ERROR
- DTC P1516: PREDICTED VS. ACTUAL THROTTLE POSITION CORRELATION ERROR
- DTC P1633: IGNITION 0 VOLTAGE LOW
- DTC P1635: 5-VOLT REFERENCE A CIRCUIT
- DTC P1639: 5-VOLT REFERENCE B CIRCUIT
- DTC P1682: IGNITION 1 VOLTAGE LOW
- Engine Controls - Basic Diagnostic Procedures: Overview
- Engine Controls - Basic Diagnostic Procedures: Diagnosis
- Engine Controls - Basic Diagnostic Procedures: Other
- Engine Controls - Trouble Shooting - No Codes: Diagnosis
- Engine Controls - Trouble Shooting - No Codes: Wiring
- Engine Controls - Trouble Shooting - No Codes: NVH
- Engine Controls - Trouble Shooting - No Codes: Other
- Engine Controls - System & Component Testing: Specifications
- Engine Controls - System & Component Testing: Overview
- Engine Controls - System & Component Testing: Diagnosis
- Engine Controls - System & Component Testing: Maintenance
- Engine Controls - System & Component Testing: Wiring
- Engine Controls - System & Component Testing: Other
- Abbreviations
- Accessories Control Systems
- Adjustments
- Airbag
- Anti-Lock/traction Control
- Application
- Automatic HVAC System
- Automatic Trans
- Auxiliary Emission Control Systems
- Axle Shafts
- Basic Trouble Shooting
- Body Electrical
- Brakes
- Charging System
- Check Lists
- Communication Devices
- Computer Relearn
- Cooling Fan
- Cooling System (Mechanical)
- Cruise Control Systems
- Diagnostic Connector Locations
- Differentials & Drive Axles
- Door Locks & Anti-Theft Systems
- Drive Cycles
- Driveline/axles
- Driveshaft & Universal Joints
- DTC Index
- Electrical Component Locations
- Electronic Suspension
- Emission Applications
- Engine
- Engine Performance
- Entertainment Systems
- Exhaust
- Exterior Body Panels
- Exterior Lights
- Exterior/interior Trim
- Frames, Subframes & Crossmembers
- Fuses & Circuit Breakers
- Gauges & Instrument Panels
- General Servicing - All Makes
- Heated Glass/defoggers
- Hoist/jack
- Horns
- Identification
- Ignition Switch/steering Lock
- Manual & Power Steering
- Manual HVAC System
- Mechanical
- Mechanical - Hydraulic
- Memory Modules
- Metric Conversions
- Mode 6
- Oem General Information
- Pin Voltage Charts
- Removal & Installation
- Reset Procedures
- Restraints
- Restraints Control Systems
- Rpo Codes
- Seats
- Sensor Range Charts
- Specifications
- Starter
- Steering
- Sun Roof/t-Top/convertible Top
- Suspension Front
- Suspension Rear
- Testing & Diagnostics
- Theory & Operation
- Transfer Case
- Transmission
- Wheel & Tire System
- Wheel Alignment
- Wiper/washer Systems
- Wiring Diagrams - Engine Performance