P0416AIR System Switching Valve B Circuit Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- 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. P0416 means the control circuit of valve B is open – the module does not see the expected level with its driver switched off. On Subaru's two-valve system valve B serves bank 2; the bulletin advises checking the valve of the other bank too, because a shared supply can be the cause. The valve stays shut and that bank gets no secondary air.
- What you may notice
- Check engine light on
- Secondary air inactive on bank 2
- Secondary air readiness not set (emission test)
- Driving normal
- Likely causes
- LikelyWire or connector to valve B open
- LikelyCoil of valve B burnt out
- PossibleShared supply of both valves faulty
- RareEngine module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €30 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.