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DTC code page

P0413: Secondary Air Injection System Switching Valve A Circuit Open

Quick answer: The valve A control circuit looks electrically open, so the ECU cannot operate the switching valve.

Drivers also search this fault as secondary air valve A circuit open, P0413 valve A open, air injection switching valve A open circuit.

Severity: medium Family: powertrain Related paths: 5
Meaning

What P0413 usually means

P0413 is the open-circuit branch of the valve A story. The controller sees missing continuity or a command path that never completes. That usually means broken wiring, unplugged or spread terminals, a burned-out valve coil, or a feed that never reaches the valve. Compared with the broader P0412, this code narrows the diagnostic path toward something disconnected or electrically absent rather than merely irrational.

Fast triage

Start here before chasing parts

  • Scan first: save freeze-frame and pending codes before clearing anything.
  • Confirm the complaint: compare the stored code with current drivability symptoms.
  • Use context: trims, live data, and related codes usually narrow the fault faster than guesswork.
  • Work simplest to hardest: leaks, connectors, maintenance items, and known patterns before expensive components.
Initial checks

What to check first

  • Verify the connector is fully seated and not oil- or water-soaked.
  • Check coil resistance for an obvious open before chasing the harness too far.
  • Inspect the harness where it bends near brackets or exhaust heat shields.
Driving risk

Can you keep driving?

P0413 is usually safe for short-term driving, but it leaves the secondary-air system offline and can delay readiness or emissions compliance.

Moderate urgency: This code often allows short-term driving, but the right fix usually comes faster when you diagnose it early instead of waiting for more codes.
Likely causes

Common causes behind this code

  • Valve A coil open internally
  • Broken control or power wire to the valve
  • Connector unplugged, corroded, or spread open
  • Lost fuse or feed to the valve circuit
  • Harness damage from heat, vibration, or previous repair work

Cause phrases often tied to this code: open valve coil, broken wire, unplugged connector, blown feed, terminal spread.

Diagnostic order

Suggested workflow

  1. Confirm the valve A circuit has supply voltage when commanded.
  2. Check continuity through the valve coil and through the harness back to the controller or relay path.
  3. Wiggle-test the harness while monitoring the circuit if the fault is intermittent.
  4. Inspect nearby shared grounds or feeds that may also affect related air-system components.
  5. After repair, verify the next cold-start event actually triggers valve function.
Avoid guesswork

Common mistakes

  • Assuming open circuit means bad ECU before checking the valve coil.
  • Looking only for broken insulation and missing spread or backed-out terminals.
  • Clearing the code without testing whether the cold-start monitor now runs correctly.
Repair path

Practical fix guidance

  • Restore a complete electrical path to valve A and confirm the valve now actuates under command.
  • If replacing the valve, inspect the connector tension so the new part is not installed onto a weak terminal fit.
  • Recheck related secondary-air codes because a lost shared feed can set more than one.
Vehicle context

Affected brands in this MVP

Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.

Aliases and common searches

English phrases tied to P0413

Useful when the driver knows the wording but not the exact DTC yet.

  • secondary air valve A circuit open
  • P0413 valve A open
  • air injection switching valve A open circuit
Related search intent

Queries this page can answer naturally

  • P0413 code meaning
  • what does P0413 mean
  • secondary air valve A open circuit
FAQ

Quick questions about P0413

What does circuit open mean on P0413?

It means the ECU sees the valve A control path as electrically broken or incomplete.

Can a blown fuse cause P0413?

Yes. If the valve loses its feed, the controller may interpret that as an open circuit.

Is P0413 different from P0412?

Yes. P0412 is a broader circuit malfunction; P0413 specifically points toward an open circuit condition.