The Waratah AS667 is a communications controller used in industrial process and motor control systems, typically interfacing with PLCs or SCADA via serial or Ethernet links. Common failure modes for this class of units include power supply degradation (brown‑out or over‑voltage on the 24 V rail), firmware corruption or bootloader lockouts, damaged UART/RS‑232 connectors, and overheating due to inadequate ventilation or dust accumulation on the PCB. First‑check diagnostics: verify that the input voltage is within spec and that the unit powers up (LED status, fan operation); inspect all serial/Ethernet connectors for bent pins or corrosion; review any error codes displayed on the unit’s LCD or communicated via diagnostic software; and perform a visual inspection of the PCB for burnt components or swollen electrolytic capacitors.[oss-gpt-20b]