The switching valve is the electrically driven valve of this path – a solenoid valve, or on Pierburg/VW systems an electric changeover valve that applies vacuum to the pneumatic combination valve; valve A serves the first path or bank 1, valve B the second. P0414 means the control circuit of valve A is shorted. A short to ground keeps the valve energized and open; a short to supply or a shorted coil overloads the driver, which many modules then switch off for the rest of the trip. An open valve with the pump running can also set P2440, and exhaust can reach the pump if the check valve leaks. Subaru names P0414 in its bulletin for the two-valve system.
Low severity. Can I keep driving?Yes, you can keep driving, though it should be repaired: the car pollutes more at startup and may not pass an inspection.
Symptoms
- Check engine light on
- Secondary air inactive
- Secondary air readiness not set (emission test)
- Driving normal
Most likely causes
- Valve coil with shorted turns (water ingress)
- Wire chafed against ground or supply
- Moisture or corrosion in the connector
- Driver in the engine module
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It affects emissions.
What each character of P0414 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 4: Emissions
- 14: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0414?
Yes, you can keep driving, though it should be repaired: the car pollutes more at startup and may not pass an inspection.
What causes code P0414?
The most common causes are: valve coil with shorted turns (water ingress); wire chafed against ground or supply; moisture or corrosion in the connector.
Related codes
- P0412AIR System Switching Valve A Circuit
- P0413AIR System Switching Valve A Circuit Open
- P0417AIR System Switching Valve B Circuit Shorted
- P2440AIR System Switching Valve Stuck Open (Bank 1)
- P0411AIR System A Incorrect Flow Detected
Sources
- static.nhtsa.gov: MC 10235914 9999
- techtips.ie: obd and secondary air system finding and remedying
- law.cornell.edu: 13 CCR 1968.2
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.