Only the towing vehicle of a semi-trailer unit is equipped with an anti-lock braking system (ABS). What could the effect of this be when performing an emergency braking manoeuvre on a wet carriageway?

The combination of selecting options 1 and 2 is correct because it highlights the potential dangers when a semi-trailer unit is missing an anti-lock braking system (ABS) on the trailer.

When only the towing vehicle is equipped with ABS and the roadway is wet, the braking distance may extend significantly because the trailer can lose traction and skid. This loss of control can lead to the trailer jack-knifing, especially if the driver applies the brakes suddenly.

Option 3, which states that the stability of the truck and trailer will be maintained during braking, is incorrect in this scenario. Without ABS on the trailer, stability cannot be guaranteed, especially in emergency situations. According to German traffic regulations, it is crucial for both the towing vehicle and the trailer to have appropriate braking systems to ensure safe operation and prevent accidents, particularly under adverse weather conditions. This emphasizes the importance of having a complete braking system on both units in a semi-trailer configuration.