P0416
PowertrainSecondary Airlow severitySecondary Air Injection System Switching Valve B Circuit Open
What P0416 Means
The PCM detected an open condition in the secondary air injection switching valve B circuit. This impacts exhaust air delivery during warm-up.
Symptoms
- Check engine light on
- Failed emissions test
- Rough cold idle
Common Causes
- Faulty switching valve B
- Open circuit wiring
- Corroded connectors
- Faulty PCM driver
Diagnostic Steps
- Scan and confirm P0416
- Inspect wiring and connectors
- Measure valve resistance
- Check PCM control output
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Community Confirmed Fixes
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