What should you do if you find that the trailer brakes are not working properly?

When trailer brakes are not functioning properly, it is crucial to prioritize safety and ensure that the vehicle is safe to operate. Taking the trailer out of service immediately is essential because operating a vehicle with malfunctioning brakes can lead to serious accidents or injuries.

Inspecting the yellow ABS malfunction lamp is also important since this lamp can indicate issues with the Anti-lock Braking System (ABS). If the ABS is not functioning correctly, it can affect overall braking performance, heightening the risk when driving.

Both actions are necessary steps to ensure the safety of the vehicle, making the combined response the most appropriate choice. This approach not only addresses the immediate safety concern by removing the vehicle from operation but also involves troubleshooting the apparent brake issue by checking the ABS lamp for any warning signals that may provide insights into the malfunction.