Leitungsbruch in der Ventilleitung

A break in the wiring to a solenoid-operated valve, so the module commands it and sees no current flow. The module cannot distinguish a broken wire from a burnt-out winding from an unplugged connector — all three read as an open circuit — and that is why this cause sits across valves in unrelated systems rather than belonging to any one of them.

The connector is the first thing to check and the likeliest finding. Valves in the emissions and recirculation systems sit on or near the engine and exhaust, where heat cycles harden the wire's insulation and vibration works terminals loose. A pin backed part-way out of its housing looks perfectly seated from outside and is one of the commonest causes here.

Where the harness breaks is predictable enough to inspect directly. Just behind the connector where the wire flexes, at a clip where the loom is held against something that moves, and anywhere the loom crosses a hot component. Test at the valve's connector rather than at the module — that splits the circuit in half in one measurement and tells you immediately whether you are looking for a wire or a winding, which is the difference between an hour with a loom and a five minute part swap.