Revision question · Braking systems

A compatible legacy tractor has red, yellow and blue brake airlines and the trailer has only red and yellow couplings. Which line needs the manufacturer’s separate instruction rather than a connection to that trailer?

Revision material from the imported DVSA bank includes source-checked Lanekind learning corrections. These corrections are not newly issued official examination questions, and practice does not reproduce a live test paper.

Answer options

Red

Yellow

Black

Blue

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BlueThis was the right answer

The blue auxiliary line needs the tractor manufacturer’s instruction. Do not improvise: incorrect handling can make the combination dangerous.

Reviewed reading for this question

Check the approved legacy coupling arrangementReviewed guidance summary · These explicitly legacy questions identify the auxiliary connection without making old diagrams universal coupling instructions.Inspect the fifth wheel before the controlled tug testReviewed guidance summary · These explicitly legacy questions identify the auxiliary connection without making old diagrams universal coupling instructions.

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