P0412 - Secondary Air Injection System Switching Valve A Circuit Malfunction

The ECM detected a fault in switching valve A circuit.

Code Overview

The ECM detected a fault in switching valve A circuit.

Common Causes

• Failed secondary air pump or valve
• Damaged relay, fuse, or wiring
• Restricted air passages or hoses

Diagnostic Steps

1. Inspect pump, valves, and hoses for damage
2. Check related fuse and relay operation
3. Command the system on and confirm airflow if supported

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

Browse the closest code-family pages when the same fault pattern often shows up nearby.

Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.