Emission controls · Powertrain · generic (SAE-defined)
P0410: Secondary Air Injection System
P0410 means the engine computer has detected a problem with the secondary air injection system, which pumps fresh air into the exhaust during cold starts to help warm the catalytic converter.
Standard title per SAE J2012 / ISO 15031-6 · Updated 2026-11-07 · By CarWhere Research
How P0410 sets
After a cold start, the powertrain control module (PCM) turns on an electric air pump and opens a check or shutoff valve to send air into the exhaust. It then watches the upstream oxygen sensors for a lean reading, or a dedicated pressure sensor, to confirm airflow. If the expected response does not occur, the PCM sets P0410. Test details are manufacturer-specific.
Common causes of P0410
Roughly most likely first; the actual cause depends on the vehicle and needs testing to confirm.
- Failed secondary air injection pump
- Stuck or failed check valve or combination valve
- Blown fuse or failed air pump relay
- Water intrusion and corrosion in the pump or valve
- Cracked or disconnected air hoses
- Carbon-blocked air passages in the cylinder head or exhaust
P0410 symptoms
- Check engine light on
- Loud whine or roar after cold start if the pump is failing
- No pump noise at all at cold start
- Usually no drivability symptoms
How P0410 is diagnosed
- Scan for codes and freeze frame; note related secondary air codes
- Listen for the pump running for the first minute or so after a cold start
- Check the pump fuse and relay, and verify power at the pump when commanded
- Inspect hoses and the check valve for cracks, water, or melting from exhaust backflow
- Command the system with a scan tool and watch upstream oxygen sensors go lean
- Check passages for carbon blockage where accessible
Typical fixes for P0410
- Replace the secondary air pump
- Replace the check or combination valve
- Replace a failed relay or fuse
- Repair hoses or clean blocked passages
Replace parts only after testing confirms the cause — a code names the circuit or condition that failed a check, not necessarily the faulty part. We don’t publish per-repair prices; for what households actually spend on upkeep, see car repair costs.
Manufacturer notes
Not all vehicles use secondary air injection. Commonly reported on some Toyota, Lexus, Volkswagen, Audi, and BMW models where pumps and valves fail from moisture.
Related codes & warning lights
P0410 FAQ
What does code P0410 mean?
P0410 means the engine computer has detected a problem with the secondary air injection system, which pumps fresh air into the exhaust during cold starts to help warm the catalytic converter. The standard definition is "Secondary Air Injection System."
Can I drive with a P0410 code?
Yes, in most cases. The system only operates briefly after a cold start, so drivability is normally unaffected, but the vehicle will likely fail an emissions inspection until it is repaired.
Why does the secondary air pump only run briefly?
Its job is to help the catalytic converter reach operating temperature quickly after a cold start. Once the engine and converter are warm, it shuts off.
Can water damage the air pump?
Yes. A failed check valve can let moist exhaust gas reach the pump, and road water can enter through its intake, causing internal corrosion.
Keep researching
More emission controls codes
Sources
- SAE J2012 — Diagnostic Trouble Code Definitions (standard code titles)
- ISO 15031-6 — Road vehicles: communication between vehicle and external equipment for emissions-related diagnostics, Part 6: Diagnostic trouble code definitions
- U.S. EPA — Vehicle Emissions Inspection and Maintenance (I/M) programs
- U.S. EPA, 40 CFR 86.1806-17 — Federal onboard diagnostics requirements for light-duty vehicles
- California Air Resources Board — On-Board Diagnostic (OBD) Program
General information written by CarWhere Research, not a diagnosis of your vehicle. Manufacturers can add their own sub-definitions and test conditions; confirm with the factory service information for your year, make and model. Before paying for a repair, check NHTSA for open recalls and your warranty booklet: federal law requires an emissions warranty on major emission-control parts such as the catalytic converter and engine computer.