Sometimes when waiting for a traffic light, I see the reversing lights on the vehicle in front of me briefly flicker on and then off again. Most often, this is on Mercedes people vans (short buses).

This startles me, since if the vehicle were to be put in reverse by accident, it would hit me when trying to drive away when the light turns green. But it always turns out to be a brief flicker of the reversing lights.

**What could be the cause of this?**

Is the driver doing something wrong, accidentally putting it in reverse? Is it faulty wiring?