P3456
Cylinder 8 Deactivation/Intake Valve Control Circuit/Open
The engine control module has detected an open or out-of-range circuit at the cylinder 8 deactivation or intake valve control solenoid. Cylinder 8 cannot be deactivated until the circuit is restored.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Solenoid coil openCommon
- Wiring or connector openPossible
- Pin pushed back out of connector bodyLess likely
Parts involved
- Cylinder Deactivation Solenoid
- Engine Wiring Harness
- ECM
P3456 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.