P0419
Secondary Air Injection System Control B Circuit
A general electrical fault on AIR system control circuit B (typically the AIR pump driver line on the second pump or relay).
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Pump driver or relay faultCommon
Parts involved
- Secondary Air Injection Pump
P0419 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.