What causes fault code P0414?

• Most likely: Internal short circuit in the SAI switching solenoid valve • Likely: Damaged wiring harness (chafed against ground or heat source) • Possible: Oxidized or melted connectors at the valve • Rare: Faulty Engine Control Unit (ECU) misinterpreting circuit load

How do you fix fault code P0414?

STEP 1: Inspect the connector to the SAI switching valve for corrosion, moisture, or heat damage. STEP 2: Use a multimeter to measure the resistance of the valve solenoid. Unplug the connector and check ohms across the pins. Normal service range is typically 20–50 Ohms. 0-2 Ohms indicates an internal short. STEP 3: Perform a continuity and short-to-ground test on the wiring harness between the valve and the ECU. STEP 4: Use a bidirectional scan tool to command the valve ON/OFF and monitor the circuit status or amperage draw. STEP 5: Replace the SAI switching valve if internal resistance is out of spec.

Powertrain (Engine & Gearbox)Standard EOBD

P0414 - Secondary Air Injection System Switching Valve A Circuit Shorted

Q: What are the symptoms of fault code P0414?

• Check engine light (MIL) illuminated • Failed emissions test (high cold-start emissions) • Possible whining sound from the air pump during the first 60 seconds after start • No noticeable driveability issues once the engine reaches operating temperature

Last updated:1 February 2026

Related:Secondary Air Valve, SAI Pump, Engine Control Unit (ECU), Secondary Air Fuse

System

Powertrain (Engine & Gearbox)

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Exhaust Gas Recirculation Flow Excessive Detected

P0403

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Technical Description

P0414 is stored when the Engine Control Unit (ECU) detects an electrical short circuit in the Secondary Air Injection (SAI) switching valve 'A' circuit. The SAI system injects fresh air into the exhaust manifold during cold starts to accelerate catalyst light-off and reduce HC and CO emissions. The ECU monitors the circuit's integrity by measuring voltage drops and current flow. A short circuit condition (to ground or power) causes a resistance value near 0 Ohms, triggering the MIL. This code specifically targets the electrical side of the solenoid valve rather than air flow issues.

Possible Causes

Internal short circuit in the SAI switching solenoid valve

Damaged wiring harness (chafed against ground or heat source)

Oxidized or melted connectors at the valve

Faulty Engine Control Unit (ECU) misinterpreting circuit load

Symptoms

Check engine light (MIL) illuminated

Failed emissions test (high cold-start emissions)

Possible whining sound from the air pump during the first 60 seconds after start

No noticeable driveability issues once the engine reaches operating temperature

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P0414 - Secondary Air Injection System Switching Valve A Circuit Shorted

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P0414 - Secondary Air Injection System Switching Valve A Circuit Shorted

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