Challenge
At the Bad Nieuweschans border crossing, German police carry out random checks on trailers. Two numbers govern almost everything about a trailer's coupling and licence plate: 1,500 kg and 750 kg. Most drivers know at most one, and on top of that mix up which safety device belongs to which weight. You will learn to keep both thresholds perfectly apart.
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The model
COUPLING (book p.231): up to 1,500 kg the trailer may have a breakaway braking device OR an auxiliary coupling; above 1,500 kg a breakaway braking device is mandatory — never both at once. PLATE (book p.231): up to 750 kg the trailer gets a white plate with the same registration as the towing car; above 750 kg the trailer gets its own registration certificate with a yellow plate and its own registration.
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Core
The coupling itself must always have an approval mark and be properly fastened, not seriously damaged, bent or rusted (book p.231) — this applies regardless of weight or which device you choose. After that it splits by weight: an UNBRAKED trailer up to 1,500 kg may run on an auxiliary coupling (a steel cable that activates the trailer's handbrake on breakaway) OR a breakaway braking device; above 1,500 kg the trailer must have a breakaway braking device. The two devices work in opposite ways and may therefore never appear together. For the licence plate, the trailer's own permitted maximum mass counts: up to 750 kg (also bike carriers that hide the car's plate from view) get a white plate with the same registration as the towing car; above 750 kg the trailer has its own registration certificate with a yellow plate and its own registration number. Before driving off you check one more thing: whether the lighting cable and the breakaway braking device or auxiliary coupling are fastened so the trailer can turn freely — up to an angle of 90 degrees — relative to the car (book p.232).
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Why it matters
A wrong coupling choice is life-threatening: if the trailer breaks free while driving, it must brake automatically — without a working breakaway device or auxiliary coupling, a detached trailer shoots unbraked onto the road. A wrong plate makes enforcement impossible: after damage it must be clear who owns the trailer, which runs through the correct registration certificate and the correct plate colour.
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Active recall
At the Bataviastad outlet market in Lelystad you buy a second-hand boat trailer with a permitted maximum mass of 1,700 kg. The seller says it has a perfectly working auxiliary coupling, nothing else. May you take it on the road like this?
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Teach back
Explain in your own words: at what weight may you choose between a breakaway brake and an auxiliary coupling, when must it be a breakaway brake specifically, and which plate colour belongs to which weight?
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Memory hook
1,500 kg: EITHER breakaway brake OR auxiliary coupling, never both. 750 kg: white-car's-own-registration becomes yellow-trailer's-own-registration.
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Frequently asked questions
‘A trailer may have both a breakaway braking device and an auxiliary coupling for extra safety’ – is that true?
No. Trailers with a breakaway braking device may NOT also have an auxiliary coupling; the two work in opposite ways (book p.231) and combining them is a defect, not extra safety.
‘An auxiliary coupling is a valid alternative to a breakaway braking device for any trailer, regardless of weight’ – is that true?
No. The choice (breakaway device OR auxiliary coupling) only applies up to 1,500 kg; above 1,500 kg a breakaway braking device is mandatory and an auxiliary coupling alone does not suffice.
‘A light trailer (up to 750 kg) gets a yellow plate with its own registration; a heavy trailer (above 750 kg) gets a white plate with the car's registration’ – is that true?
No. It is exactly the reverse. Up to 750 kg: white plate with the towing car's registration. Above 750 kg: own registration certificate with a yellow plate and its own registration number.
‘A bike carrier mounted at the rear of the car does not need its own licence plate because it is not a real trailer’ – is that true?
No. The same up-to-750-kg rule applies to bike carriers that hide the car's licence plate from view. They get a white plate with the same registration as the car.
‘Under 1,500 kg with a working auxiliary coupling, the coupling itself does not need an approval mark’ – is that true?
No. The coupling of every trailer must always have an approval mark and be properly fastened, regardless of weight or which braking device was chosen.