P3405Cylinder 1 Exhaust Valve Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- J2012 reserves P3405 for an open control circuit of a separate exhaust valve actuator on cylinder 1. No manufacturer documents this code publicly. The common systems do not need it: in GM's Dynamic Fuel Management one solenoid per cylinder feeds oil to both intake and exhaust lifters, and Ford's VDE only lists intake codes for cylinder 1. A GM patent application uses one shared hydraulic valve and only sets the order, with the exhaust valves switched off and back on before the intake valves; a Ford patent watches the exhaust valve via exhaust pressure. A separate exhaust actuator would fall under CARB's output component rule, which asks for continuity checks. If used, an open coil or wire would set P3405, while P3401 covers the intake side and P3406-P3408 the other exhaust faults.
- What you may notice
- Check engine lamp on
- Cylinder deactivation or valve switching disabled
- Likely causes
- PossibleBroken wire or loose terminal to the exhaust valve actuator
- PossibleOpen coil in the cylinder 1 exhaust valve actuator
- RareOutput driver fault in the engine control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.