Fault Family System: Powertrain (P-Codes) 20 SAE Codes

Secondary Air Injection System

Diagnostic & Technical Explanation

Code P0410 (AIR System A) sets when the ECM commands the secondary air injection system (used to inject fresh air into the exhaust during cold start to speed catalyst light-off and reduce emissions) and detects incorrect flow, an open/shorted switching valve circuit, or a control circuit fault. Causes are a seized or failed AIR pump, a stuck or corroded switching/check valve, a collapsed or leaking air delivery hose, or damaged wiring to the pump/valve.

These 20 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 20 times.

Codes in this family (20)

Code	Definition	Repair coverage
P0410	AIR System A	4 ranked fixes
P0411	AIR System A Incorrect Flow Detected	4 ranked fixes
P0412	AIR System Switching Valve A Circuit	4 ranked fixes
P0413	AIR System Switching Valve A Circuit Open	4 ranked fixes
P0414	AIR System Switching Valve A Circuit Shorted	4 ranked fixes
P0415	AIR System Switching Valve B Circuit	4 ranked fixes
P0416	AIR System Switching Valve B Circuit Open	4 ranked fixes
P0417	AIR System Switching Valve B Circuit Shorted	4 ranked fixes
P0418	AIR System Control A Circuit	4 ranked fixes
P0419	AIR System Control B Circuit	4 ranked fixes
P041F	AIR System Switching Valve A Circuit Low	4 ranked fixes
P044F	AIR System Switching Valve A Circuit High	4 ranked fixes
P0491	AIR System Insufficient Flow Bank 1	4 ranked fixes
P0492	AIR System Insufficient Flow Bank 2	4 ranked fixes
P2257	AIR System Control A Circuit Low	4 ranked fixes
P2258	AIR System Control A Circuit High	4 ranked fixes
P2259	AIR System Control B Circuit Low	4 ranked fixes
P2260	AIR System Control B Circuit High	4 ranked fixes
P25F6	AIR System B	4 ranked fixes
P25F7	AIR System B Incorrect Flow Detected	4 ranked fixes

What this page does not show

This page publishes the fault mechanism and the code index. The licensed dataset adds, for every one of the 15,886 codes, the full authored repair set (56,729 procedures in total) with the fields deliberately withheld here:

Procedures 2..n after the first-listed procedure
Aftermarket parts cost ranges in USD (est_parts_cost_min/max_usd)
Professional labor-hour estimates (est_labor_hours)
Step-by-step diagnostic and repair instructions
Replacement-part mappings and catalog lookups
6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)

Need All 15,886 Codes as Data?

Pipe-delimited CSV, Apache Parquet and a relational SQLite database, with commercial application rights and instant download. Built for scan tools, shop software and research - not assembled one web page at a time.

License OEM Complete · $149 Standard (SAE only) · $49

$49 Standard: 9,249 SAE codes · $149 OEM Complete: all 15,886 codes, including 6,637 OEM codes across 32 makes · $149 Heavy Duty: 4,212 fault pairs (J1939) · one-time · compare tiers