Failures here are usually mechanical — a torn speaker cone, a fogged camera lens, a broken antenna mast — rather than electronic.
Radio and display units vary by option content. A head unit from a vehicle with premium audio carries different amplification and speaker-level outputs from the base unit, and a camera from a vehicle with a 360-degree system is not the same part as the reversing camera. The catalogue qualifiers on each listing record those differences.
Where a radio or display needs coding to the vehicle, the listing says so, and the work needs the manufacturer's diagnostic software rather than a generic scan tool.
