What is checked during a trailer inspection?
A trailer roadworthiness inspection checks whether your trailer is safe to use on public roads. All safety-relevant components are examined – in particular the brakes, lighting, tyres, and structural parts. Inspection rules and procedures vary by country, so always check what applies in your region.
Main inspection points
While the exact procedure differs between countries, the following areas are checked in most European roadworthiness inspections:
– Brake system and braking performance
– Lighting and electrical system
– Tyres, rims, and tyre pressure
– Coupling and connection to the towing vehicle
– Axle, frame, and load-bearing components
– General condition and safety
Brakes and overrun brake
The brakes must operate evenly and reliably on both sides. Problems are often caused by incorrect adjustment or worn components. The brake shoes and brake cables are typical wear parts that should be inspected in advance. The overrun brake is also checked – it must engage smoothly and release fully. For guidance on adjustment see how to adjust trailer brakes, and for fault diagnosis see overrun brake not working.
Lighting and electrics
All lights must work correctly – rear lights, brake lights, indicators, and number plate lighting. Electrical connections and wiring are also checked for damage or poor contact. Make sure your trailer lighting is fully functional before the inspection date. For an overview of lighting requirements see the trailer lighting guide.
Tyres, rims, and tyre pressure
Tyres must have sufficient tread depth and must be free from damage, bulges, or cracks. Tyre pressure must match the manufacturer’s specification. Check your tyres carefully in advance – see the guide on trailer tyre pressure.
Coupling and safety devices
The coupling head must close securely and must not show excessive play or wear. The breakaway cable is also inspected – it must be correctly fitted and in good condition.
Axle, frame, and load-bearing parts
The axle and frame must be free from significant damage or corrosion. Wheel bearings are checked for play or roughness. The trailer must not be loaded beyond its rated axle capacity – for more on this see the guide on trailer axle load.
Typical defects found at inspection
– Uneven or insufficient braking force
– Faulty lighting or electrical connections
– Worn or damaged tyres
– Play or wear in the coupling
– Corrosion on structural parts
If your trailer does not pass, see the guide on trailer failed inspection for next steps.
How to prepare for a trailer inspection
Go through each of the areas above before the inspection date. Replace worn parts in good time – brake shoes, brake cables, and lighting are the most common causes of failure and are straightforward to address in advance. For a full preparation guide see trailer inspection – checklist and common defects.
Summary
A trailer inspection covers all safety-critical components – brakes, lighting, tyres, coupling, and structure. Regular maintenance and timely replacement of worn parts give the best chance of passing without issues. Rules and procedures vary by country, so always verify what applies in your region.