P0413
Secondary Air Injection System Switching Valve A Circuit OpenP0413 is a generic OBD-II powertrain diagnostic trouble code: Secondary Air Injection System Switching Valve A Circuit Open. It is logged by the engine control unit when the egr monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.
What P0413 means
P0413 is stored when the PCM detects an open circuit in the Secondary Air Injection (SAI) system switching valve "A" control circuit. The secondary air injection system improves cold-start emissions by pumping ambient air directly into the exhaust stream immediately after a cold start, supplying the extra oxygen needed to oxidise unburned hydrocarbons and carbon monoxide before the catalytic converter reaches operating temperature. Switching valve "A" controls the airflow path on the primary bank (or the sole bank on inline engines).
An open-circuit fault means the PCM is commanding the switching valve solenoid to energise but is detecting no current draw — or is measuring a voltage level that indicates the circuit is broken rather than connected. Common causes are a disconnected or corroded connector, a broken wire in the solenoid harness, a failed solenoid with an open winding, or a blown fuse protecting the secondary air circuit. Unlike a shorted circuit (P0414), an open circuit will not damage the pump or discharge the battery; however, the switching valve will remain closed and no secondary air will enter the exhaust.
The practical result is elevated cold-start emissions and potential catalyst warm-up delay. On vehicles with strict OBD monitoring the MIL will illuminate. Drivability impacts are typically minor — possible cold-start hesitation or an audible change in pump noise — because the fault only affects the emissions-control phase of a cold start, not normal engine operation.
Common causes
Most-frequently reported root causes when P0413 is logged.
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1
Open circuit in the switching valve "A" solenoid wiring — broken wire, chafed insulation, or severed harness.
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2
Corroded, loose, or disconnected electrical connector at the switching valve "A" solenoid.
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3
Failed switching valve solenoid with an open winding, producing no current draw when commanded.
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4
Blown fuse in the secondary air injection system supply circuit.
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5
Damaged wiring caused by heat from nearby exhaust components.
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6
Condensation or water ingress into the connector causing intermittent open-circuit behaviour.
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7
Faulty PCM output driver for the switching valve "A" circuit (rare).
Symptoms drivers notice
How to diagnose P0413
A typical diagnostic flow when this code is present.
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1
Connect a scan tool and confirm P0413; check for companion codes such as P0410 (system fault), P0412 (switching valve A generic), or P0414 (valve A shorted).
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2
Inspect the switching valve "A" connector and wiring harness for disconnection, corrosion, broken wires, or heat damage.
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3
Check and replace the secondary air injection fuse if blown; investigate the root cause if the fuse has blown repeatedly.
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4
With the ignition on and using a scan tool actuator test to command the valve on, measure voltage at the solenoid connector — battery voltage should be present when commanded on.
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5
Measure solenoid winding resistance; an open winding (OL / infinite resistance) confirms a failed solenoid.
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6
Check circuit continuity from the PCM output to the solenoid connector, verifying no open section exists in the harness.
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7
If voltage is reaching the solenoid and resistance is within specification but the code persists, check the PCM output side for a driver fault.
Related powertrain codes
- P0400 — Exhaust Gas Recirculation Flow Malfunction
- P0401 — Exhaust Gas Recirculation Flow Insufficient Detected
- P0402 — Exhaust Gas Recirculation Flow Excessive Detected
- P0403 — Exhaust Gas Recirculation Circuit Malfunction
- P0404 — Exhaust Gas Recirculation Circuit Range/Performance
- P0405 — Exhaust Gas Recirculation Sensor A Circuit Low
Frequently asked questions
What is the difference between P0413 and P0412?
P0412 is a generic switching valve "A" circuit malfunction — it does not specify whether the circuit is open or shorted. P0413 is the more specific variant confirming the circuit is open (no current path). P0413 gives a clearer diagnosis direction: look for disconnected connectors, broken wires, or a solenoid with an open winding.
Will P0413 cause me to fail an emissions test?
Yes, in most jurisdictions. The secondary air injection system is an emissions-critical system and an active P0413 will illuminate the MIL. A lit MIL is an automatic fail at most OBD-based emissions inspections, regardless of whether the actual tailpipe emissions are elevated.
Can I drive with P0413?
The vehicle will drive normally under warm conditions. The impact is limited to cold-start emissions performance. However, because the MIL is on and the secondary air system is non-functional, the fault should be repaired to restore emissions compliance and prevent catalyst degradation from repeated cold starts without secondary air.
Is the open circuit always in the wiring, or can the solenoid itself fail open?
Both are common. Solenoid windings can fail open as the coil wire breaks internally due to heat cycling and vibration. Wiring harness damage — particularly near exhaust manifolds where heat is high — is equally common. Measuring solenoid resistance at the component (not just at the PCM connector) will differentiate between an internal solenoid failure and a wiring/connector fault.
Disabling P0413 in software
RaceTune can permanently disable P0413 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.
Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.
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