Check Heated Oxygen Sensors (HO2S) following procedures in DTC P0131 , DTC P0132 and DTC P0136. Repair as necessary. If HO2S is okay, replace TWC. Retest system.
Home/Suzuki/X-90/Suzuki X-90 I (1995-2000)/Repair manual/Testing & Diagnostics/DTC P0420: THREE-WAY CATALYST (TWC) SYSTEM EFFICIENCY LOW
Contents
Wiring diagrams Section: Testing & Diagnostics- Engine Controls - Basic Testing: Diagnosis
- Engine Controls - Basic Testing: NVH
- Engine Controls - Basic Testing: Other
- Engine Controls - Tests W/codes: Diagnosis
- Engine Controls - Tests W/codes: Maintenance
- Engine Controls - Tests W/codes: Component Locations
- Engine Controls - Tests W/codes: Other
- DTC P0101: MASS AIRFLOW (MAF) CIRCUIT PERFORMANCE PROBLEM
- DTC P0102: MASS AIRFLOW (MAF) CIRCUIT LOW INPUT
- DTC P0103: MASS AIRFLOW (MAF) CIRCUIT HIGH INPUT
- DTC P0112: INTAKE AIR TEMP. (IAT) SENSOR CIRCUIT LOW INPUT
- DTC P0113: INTAKE AIR TEMP. (IAT) SENSOR CIRCUIT HIGH INPUT
- DTC P0117: ENGINE COOLANT TEMP. (ECT) SENSOR CKT LOW INPUT
- DTC P0118: ENGINE COOLANT TEMP. (ECT) SENSOR CKT HIGH INPUT
- DTC P0121: THROTTLE POSITION (TP) SENSOR SYSTEM PERFORMANCE
- DTC P0122: THROTTLE POSITION (TP) SENSOR CIRCUIT LOW INPUT
- DTC P0123: THROTTLE POSITION (TP) SENSOR CIRCUIT HIGH INPUT
- DTC P0125: EXCESSIVE TIME TO ENTER CLOSED LOOP
- DTC P0131: HEATED O2 SENSOR (HO2S) NO. 1 CIRCUIT VOLTAGE LOW
- DTC P0132: HEATED O2 SENSOR (HO2S) NO. 1 CIRCUIT VOLTAGE HIGH
- DTC P0133: HEATED OXYGEN SENSOR (HO2S) NO. 1 SLOW RESPONSE
- DTC P0134: HEATED O2 SENSOR (HO2S) NO. 1 CKT ACTIVITY INSUFFICIENT
- DTC P0136: HEATED O2 SENSOR (HO2S) NO. 2 CKT MALFUNCTION
- DTC P0141: HEATED O2 SENSOR (HO2S) NO. 2 HEATER CKT MALFUNCTION
- DTC P0171: FUEL TRIM SYSTEM LEAN
- DTC P0172: FUEL TRIM SYSTEM RICH
- DTC P0300: RANDOM MISFIRE
- DTC P0301, P0302, P0303 OR P0304: CYLINDERS NO. 1-4 MISFIRE
- DTC P0335: CRANKSHAFT POSITION (CKP) SENSOR CKT MALFUNCTION
- DTC P0340: CAMSHAFT POSITION (CMP) SENSOR CKT MALFUNCTION
- DTC P0400: EXHAUST GAS RECIRCULATION (EGR) FLOW MALFUNCTION
- DTC P0420: THREE-WAY CATALYST (TWC) SYSTEM EFFICIENCY LOW
- DTC P0440: EVAPORATIVE (EVAP) CONTROL SYSTEM MALFUNCTION
- DTC P0443: EVAPORATIVE (EVAP) CONTROL SYSTEM PURGE FLOW INCORRECT
- DTC P0455: EVAPORATIVE (EVAP) CONTROL SYSTEM LEAK DETECTED
- DTC P0461: FUEL LEVEL SENSOR CIRCUIT PERFORMANCE
- DTC P0463: FUEL LEVEL SENSOR CIRCUIT VOLTAGE HIGH
- DTC P0500: VEHICLE SPEED SENSOR (VSS) MALFUNCTION
- DTC P0505: IDLE AIR CONTROL (IAC) SYSTEM MALFUNCTION
- DTC P0510: CLOSED THROTTLE POSITION (CTP) SWITCH MALFUNCTION
- DTC P0601: PCM MEMORY ERROR OR
- DTC P0603: KEEP ALIVE MEMORY ERROR
- DTC P1408: MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR CKT MALFUNCTION
- DTC P1410: FUEL TANK PRESSURE CONTROL SYSTEM MALFUNCTION
- DTC P1450: BAROMETRIC PRESSURE SENSOR CIRCUIT MALFUNCTION OR
- DTC P1451: BAROMETRIC PRESSURE SENSOR PERFORMANCE PROBLEM
- DTC P1500: ENGINE STARTER SIGNAL CIRCUIT MALFUNCTION
- DTC P1510: ECM BACKUP POWER SUPPLY MALFUNCTION
- DTC P1530: IGNITION TIMING ADJUSTMENT SWITCH CKT MALFUNCTION
- DTC P1715: PARK NEUTRAL POSITION (PNP) SWITCH CKT MALFUNCTION
- Engine Controls - System/component Tests: Specifications
- Engine Controls - System/component Tests: Diagnosis
- Engine Controls - System/component Tests: Other
- Abbreviations
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- Wiring Diagrams - Engine Performance