OBD-II code · Powertrain (manufacturer / generic)

P3466 Cylinder Deactivation Hydraulic Circuit Bank 1 Open

The engine control module has detected an open hydraulic circuit in the cylinder deactivation system on bank 1. The system uses pressurized engine oil routed through dedicated lifters and oil control valves to collapse valves; an open circuit indicates loss of oil flow or a failed pressure switch.

Is it safe to drive with P3466?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyOil pressure switch failed
  • PossibleOil passage blocked or sludge buildup
  • PossibleOil control valve stuck

Repair at a glance

Difficulty
Shop_only
DIY friendly
Best left to a mechanic
Typical labour
2–10 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Oil Control Valve, Oil Pressure Switch, Lifter, Engine Oil Passage

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.