P0413
UniversalSecondary Air Injection System Switching Valve A Circuit Open
The secondary air injection system sends air into the exhaust, commonly to help reduce emissions during certain operating conditions. This code means the vehicle detected an open electrical circuit in the control circuit for switching valve A. The valve may not operate as intended, which can increase emissions or trigger the check-engine light; the code alone does not prove the valve itself has failed.
⚠️ Before You Begin (Safety First)
This fault is usually not an immediate driving emergency, but emissions may be higher and the vehicle may fail an emissions inspection. Keep hands and tools away from hot exhaust components. Stop driving and seek help if the vehicle develops serious drivability problems or another warning indicates an immediate safety issue.
Common Symptoms
- The check-engine light may be on because the system detected an open valve-control circuit.
- There may be no noticeable change in how the vehicle drives, since this system primarily affects exhaust emissions.
- The secondary air system may not operate as intended, potentially increasing emissions during the conditions when it is used.
- The vehicle may fail an emissions inspection if the fault or resulting emissions issue is present.
Common Causes
- A damaged, disconnected, or corroded connector may interrupt the valve circuit.
- A broken or damaged wire may leave the circuit open.
- The switching valve may have an internal electrical open, though testing is needed to establish this.
- A fuse, power supply, ground, or control-side fault may interrupt the circuit, depending on the vehicle's design.
- A control-module or driver fault is possible but should be considered only after the circuit and valve are checked.
Diagnostic Steps
- Confirm the stored code with a scan tool and note any related codes; related faults can help guide diagnosis.
- With the vehicle off and cool, visually inspect accessible wiring and connectors for looseness, corrosion, chafing, or obvious damage.
- Check the vehicle-specific owner's information for a relevant fuse and inspect it if accessible; replace only with the specified type and rating.
- Avoid applying power directly to the valve or probing unidentified terminals. If the visible checks do not reveal the issue, have the circuit tested using vehicle-specific service information.
When to Call a Professional
Use vehicle-specific service information to identify the correct circuit and test points. A technician can inspect scan data, check the valve and wiring for an open circuit, verify power and control signals, and determine whether the fault is in the valve, connections, wiring, or control electronics before replacing parts.
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Commonly Asked Questions
Does P0413 mean the switching valve must be replaced?
No. It identifies an open circuit in the valve A control circuit, not a confirmed failed valve. Wiring, connectors, power supply, or control electronics can also cause an open circuit.
Can I keep driving with P0413?
If the vehicle otherwise runs normally, this code alone is not usually an immediate driving emergency. Arrange diagnosis because emissions may be affected, and stop driving if serious drivability or safety problems develop.
What does “circuit open” mean here?
It means the monitored electrical path for switching valve A appears interrupted. The exact monitoring method and circuit layout depend on the vehicle.
Could the vehicle feel normal even with this code?
Yes. The secondary air system mainly supports emissions control, so an electrical fault may turn on the check-engine light without an obvious change in everyday driving.
Browse Available Code Guides
Previous and next available guides in database record order, across makes. Adjacent entries may share a code number and do not necessarily describe related faults.