A safety-related communication system includes a safety relay with signal inputs of an input signal current circuit that connect the safety relay to a control device for monitoring the input signal circuit. The safety relay also includes at least two load outputs of a load current circuit for connecting to a load. Switching elements are connected in parallel and configured to switch the load current circuit on or off based on an activation signal at the input signal current circuit. A diagnostic device monitors faults in the load current circuit and/or the safety relay. A signaling device connected to the signal inputs provides an impedance for the input signal circuit. The impedance is tuned to the control device during a fault-free state and is detunable upon detection of a fault so as to signal the detected fault to the control device via the input signal current circuit.