Your boiler's computer has detected a conflict between its internal sensors or a wiring fault, causing it to shut down for safety.

Fault: Electronics/sensor - Electronics, safety-relevant sensor or cable defective

What causes this fault?

This fault occurs when the boiler's control center receives conflicting temperature readings that don't match up, triggering an emergency safety shutdown. The most common reason is a physical short circuit in the internal wiring or a specific electronic component failing due to moisture or age. It essentially means the boiler can no longer trust its own sensors to monitor heat levels safely.