دائرة مفتوحة في أسلاك الحالة

A break in a wire carrying a status or feedback signal between systems, so a module cannot confirm the state of something it depends on. It is distinct from a control circuit — nothing is being commanded down this wire, only reported — which is why the controlled function often continues to work.

On a hybrid or electric vehicle these lines carry safety-relevant states: whether a contactor has closed, whether an interlock is intact, whether a charge connector is engaged. A module unable to confirm such a state will assume the unsafe case and refuse to proceed, which is correct behaviour and produces a vehicle that will not run or will not charge.

Test at both ends before opening the harness, since the fault is a wire rather than a device, and check the connectors first — corrosion and a backed-out terminal are commoner than a broken conductor. Never bridge a status line to satisfy a module: it exists to report a real condition, and defeating it defeats the protection that depends on it.