Powertrain, generic · Auxiliary emission controls

P0414 AIR System Switching Valve A Circuit Shorted

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

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.

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

Symptoms

  • Check engine light on
  • Secondary air inactive
  • Secondary air readiness not set (emission test)
  • Driving normal

Repair estimate

DifficultyEasyDIY possible
Parts and labour€30–300
Time0.3–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

air switching valve aair combination valvevalve wiringengine control module

Related codes

P0412P0413P0417P2440P0411

References: static.nhtsa.gov, techtips.ie, law.cornell.edu.