Manocontact de levée de soupape défectueux

The switch confirming that oil pressure has actually reached a variable valve lift actuator, which is the feedback half of a system whose control half is a solenoid. The module commands lift, then waits to be told the oil arrived — and if it is not told, it will not proceed, because switching lift mechanisms without pressure risks the mechanism itself.

So a switch fault disables a healthy system. Lift changes are suppressed, the engine runs permanently on one profile, and the complaint is a flat top end or poor low-speed running depending on which profile it is stuck in. The mechanism, the solenoid and the oil supply may all be perfect, and the codes name actuator performance rather than the switch.

Oil condition matters more here than almost anywhere. These switches and the fine screens feeding them block with sludge, so a vehicle with extended or missed oil changes produces this fault with a switch that is mechanically fine. Check the oil's condition and level, and the screen behind the solenoid, before ordering a switch. A switch reporting no pressure may also be telling the truth — genuinely low oil pressure at that gallery gives the same code, and that is a much more serious finding worth ruling out first.