When should you arrange for the braking system of your car to be checked?

Your answer correctly identified the situations when the braking system should be checked. Under German traffic regulations, it is crucial to monitor the condition of your vehicle's braking system for safety reasons.

The brake control light illuminating indicates a malfunction that needs immediate attention. Additionally, if your car fails to stay in line when braking, this suggests a problem with the brake system, possibly with the brake balance or performance, which can significantly affect vehicle control.

In contrast, while performing an emergency braking maneuver can indicate the need for a brake system check, it is not a standalone reason because emergency situations can occur even with a functioning brake system. However, if the emergency braking causes issues, it would warrant a check, but it's less direct than the first two choices.

Thus, the first two points directly relate to identifiable problems with the brakes that require immediate checking, reflecting the importance of vehicle safety compliance under German laws. Ensuring that your brakes are in perfect condition is essential for your safety and that of other road users.