P0412
PowertrainEmission Controlslow severitySecondary Air Injection System Switching Valve A Circuit
What P0412 Means
Malfunction in the AIR switching valve circuit.
Symptoms
- Check Engine Light
- AIR system not functioning
Common Causes
- Faulty switching valve
- Wiring issue
- Relay failure
Diagnostic Steps
- Test valve solenoid
- Check wiring
- Test relay
Where to start: Replace switching valve or repair wiring.
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