PowertrainP0426

Caution

Severity: Caution - get it checked when you can

Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1)

26 brands affected · Generic SAE J2012 description.

Key terms: Catalytic converter: cleans the exhaust gases · EGR: exhaust gas recirculation, which cuts harmful gases · EVAP: the system that traps fuel vapour · Oxygen sensor: measures oxygen in the exhaust gas · Bank 1: the side of the engine containing cylinder 1 · SAE J2012: the standard generic code list · Powertrain: engine, transmission and emissions

1What it means in plain English

This range covers emissions control (EGR, EVAP, oxygen sensors and the catalytic converter), but some manufacturers also use P04 codes for oil-pressure, brake-fluid and coolant-level warnings.

2Common causes

Clogged or faulty EGR valve
EVAP system leak (hoses, canister, fuel cap)
Faulty oxygen sensor
Ageing catalytic converter
Low oil, brake fluid or coolant (on some models)
Wiring or connector fault

3Can I drive?

Caution · drive with care

Do not assume this code is safe to drive. Check the description: if it names oil pressure, brake fluid, coolant, or a brake fault, stop safely and have it diagnosed before driving. Emissions-only codes (EGR, EVAP, catalyst) should still be checked before an emissions or roadworthiness inspection.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 26

Brand	Code	Description	System
Ashok Leyland CV	P0426	Cylinder 6. Fuel Injector. Control Module B. Open Circuit Brand	Powertrain
BAIC Motor	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
Mercedes-Benz	P0426	Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) SAE	Powertrain
BMW	P0426	Catalyst Temp. Sensor Bank1 Range/Perf Brand	Powertrain
BYD	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
Chery	P0426	Catalyst Temp Sensor: Bank 1 (G20): Implausible Signal Brand	Powertrain
Daewoo	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
DFFS	P0426	Immobilizer authentication failed Brand	Powertrain
DFFX	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
DFXK	P0426	DOC upstream temperature sensor signal implausible Brand	Powertrain
EOBD	P0426	Julat/prestasi litar sensor suhu pemangkin bank 1 sensor 1 Brand	Powertrain
Geely	P0426	Catalyst Temp Sensor: Bank 1 (G20): Implausible Signal Brand	Powertrain
GM	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
Great Wall	P0426	Oxidation catalyst converter upstream temperature implausible Brand	Powertrain
Hafei	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
Holden	P0426	Exhaust Gas Temperature Sensor 1 Performance Brand	Powertrain
Hyundai	P0426	Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) SAE	Powertrain
Isuzu	P0426	Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) SAE	Powertrain
Land Rover	P0426	Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) SAE	Powertrain
Maserati	P0426	Catalyst temperature sensor circuit performance (bank 1 sensor 1) Brand	Powertrain
Opel	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
Peugeot	P0426	Catalyst Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) SAE	Powertrain
Saab	P0426	Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 Brand	Powertrain
MG (SAIC)	P0426	Pre Catalyst Temperature Sensor Range/Performance Brand	Powertrain
Tata	P0426	Catalyst Temperature Sensor Range/Performance Bank 1 Brand	Powertrain
Toyota	P0426	Immobilizer authentication failed Brand	Powertrain

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Extended variant codes 1

These 7-character codes are manufacturer-specific variants of P0426 and may be reported by some scan tools.

Brand	Code	Description	System
Mercedes-Benz	P042627	Der Temperatursensor 1 'Katalysator' (Zylinderreihe 1) hat Funktionsstörung.Signaländerungsrate ist oberhalb des zulässigen Grenzwertes. Brand	Powertrain

6Related codes

Browse Pxxx codes or P042xx codes.