Secondary Air Injection Switching Valve B Circuit Open
The P0416 code indicates that the Engine Control Module (ECM) has detected an open circuit in the secondary air injection system switching valve B. This valve controls the flow of air from the air pump to the exhaust manifold to reduce emissions during cold starts. An open circuit means there is a break in the electrical path, preventing the valve from operating correctly.
01. Most Common Causes
- Faulty secondary air injection switching valve B
- Open or shorted wiring in the valve circuit
- Blown fuse or relay for the secondary air injection system
- Corroded or loose electrical connector at the valve
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Failed emissions test
- Possible rough idle or hesitation on cold start
- No audible air pump operation during cold start
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P0416 and check for related codes.
Step 2: Visually inspect the wiring and connector for damage, corrosion, or loose connections.
Step 3: Test the valve's resistance with a multimeter; compare to manufacturer specs.
Step 4: Check for power and ground at the valve connector with the engine cold and key on.
Step 5: If power and ground are present, replace the valve. If not, trace the circuit for opens or shorts.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive, but the vehicle may fail an emissions test and the Check Engine Light will remain on. It is recommended to repair it soon to avoid potential issues with cold start performance.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the cause. If the valve needs replacement, parts cost around $30-$80, and labor adds $20-$70.