Secondary Air Injection System Control B Circuit Low
The drive line for secondary air injection (AIR) control circuit B is stuck low. Secondary air is pumped into the exhaust manifold during cold start to speed up catalyst light-off.
Affected components
- Secondary air injection pump
- Secondary air injection valve
Common causes
- High likelihood: Short to ground
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Harness chafing through insulation
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.