You want to tow a trailer. What must you note regarding the electric cable between the towing vehicle and the trailer?

You answered correctly. When towing a trailer, it is essential to ensure that the electric coupling devices are not damaged, so the connection between the vehicles is safe and reliable. The onboard voltage of the towing vehicle and the trailer must be the same, so the electrical systems work together without causing faults. Finally, you must always check that all the lighting systems—such as brake lights, indicators, and tail lights—are working properly before you drive, ensuring both your own and other road users' safety. These checks are required by German traffic regulations whenever you use a trailer.