PowertrainP0418

Caution

Severity: Caution - get it checked when you can

AIR System Control A Circuit

31 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 · 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 31

Brand	Code	Description	System
Ashok Leyland CV	P0418	AIR System Control A Circuit SAE	Powertrain
BAIC Motor	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
Mercedes-Benz	P0418	AIR System Control A Circuit SAE	Powertrain
BMW	P0418	Open circuit Brand	Powertrain
BYD	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
Chery	P0418	SLS Secondary Air Pump Control Circuit Fault Brand	Powertrain
Daewoo	P0418	Secondary Air Pump Malfunction Brand	Powertrain
DFFS	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
DFFX	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
DFXK	P0418	Secondary air pump control circuit fault Brand	Powertrain
EOBD	P0418	Luftsystemkontroll 'A'-krets Brand	Powertrain
Geely	P0418	SLS 2nd air pump Contr. Circ. malf Brand	Powertrain
GM	P0418	AIR pump relay control circuit bank 1 Brand	Powertrain
Great Wall	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
Hafei	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
Holden	P0418	Secondary Air Injection Pump Control Circuit Brand	Powertrain
Hyundai	P0418	AIR System Control A Circuit SAE	Powertrain
Isuzu	P0418	AIR System Control A Circuit SAE	Powertrain
Land Rover	P0418	AIR System Control 'A' Circuit Brand	Powertrain
Maserati	P0418	Secondary Air Injection System Control Circuit Brand	Powertrain
Opel	P0418	AIR pump relay control circuit bank 1 Brand	Powertrain
Peugeot	P0418	AIR System Control A Circuit SAE	Powertrain
Porsche	P0418	AIR System Control A Circuit SAE	Powertrain
Saab	P0418	AIR Pump Relay Control Circuit Bank 1 Brand	Powertrain
MG (SAIC)	P0418	Secondary Air Injection System Control A Circuit Brand	Powertrain
Smart	P0418	AIR System Control A Circuit SAE	Powertrain
Subaru	P0418	Sec. Air Pump Relay Brand	Powertrain
Tata	P0418	Secondary Air Injection System Control 'A' Circuit Brand	Powertrain
Toyota	P0418	Air system control 'A' circuit Brand	Powertrain
Volvo	P0418	Electric Air Pump Primary Brand	Powertrain
Volkswagen	P0418	Relay for secondary air injection pump (J299): malfunction; Short to ground 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 P0418 and may be reported by some scan tools.

Brand	Code	Description	System
Mercedes-Benz	P041800	Die Ansteuerung des Sekundärluftsystems 1 (Luftpumpe) hat einen elektrischen Fehler. Brand	Powertrain

6Related codes

Browse Pxxx codes or P041xx codes.