P0410
Secondary Air Injection System
Low· Fix when convenientIntermediatePowertrainGeneric, all makes
What it means
The secondary air injection system, which pumps fresh air into the exhaust for a minute or two after a cold start to heat up the catalytic converter, is not working correctly.
Is it safe to drive?
Safe to drive. It only works briefly after cold starts.
Symptoms
- Check engine light on
- Loud whining or humming from the air pump after cold start, or no sound at all
Probable causes
Most likely first
- 1Failed air pump (often from water getting in)
- 2Stuck or leaking check valve
- 3Blown fuse or failed relay
- 4Cracked hoses
How to diagnose it
Work through these in order before buying parts
- 1Record the code and its freeze frame data (speed, load, temperature when it set), then clear it and see if it comes back.
- 2Listen for the pump running for about a minute after a cold start.
- 3Check the fuse and relay.
- 4Inspect hoses and the check valve for blockage or melted parts.
- 5Check for technical service bulletins (TSBs) or software updates for your make and model; some codes have known factory fixes.
Common fixes
- Replace the air pump
- Replace the check valve
- Replace the relay or fuse
This information is general guidance for all makes. Exact causes, specifications and procedures vary by vehicle, so confirm with your service manual or a qualified mechanic before replacing parts.