What may happen if you apply trailer brakes only on slippery roads?

Applying trailer brakes only on slippery roads can lead to wheels locking up, which in turn causes skidding. This occurs because the braking force can exceed the available traction between the tires and the slippery surface. When the wheels lock up, they stop turning and begin to slide, which can significantly impair steering control and increase the risk of losing control of the vehicle.

In slippery conditions, it's crucial to maintain control over both the vehicle and trailer to prevent accidents. Optimal braking involves using both the tow vehicle's and the trailer's brakes in a balanced manner to ensure that the vehicle remains stable. When only the trailer brakes are applied, there can be an imbalanced situation that exacerbates the risk of skidding. Properly managing brake application on slippery roads is essential for safe driving.