TorqueMech OBD Code Guide
P0412 - Secondary Air Injection System Switching Valve A Circuit Malfunction
The ECM detected a fault in switching valve A circuit.
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Read code pattern
Check likely system
Estimate after confirmation
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
- Inspect pump, valves, and hoses for damage
- Check related fuse and relay operation
- Command the system on and confirm airflow if supported
Related OBD Codes
Browse nearby codes when systems overlap.
Next Steps
Move from code to checks, then estimate.