In New York cabs, blinking amber trouble lights are meant to summon the police.
The lights are part of a taxi’s emergency signaling equipment. A round amber light is mounted near the left side of the trunk, with another amber light at the front, usually concealed behind the grille. When the driver activates them, they blink to signal that police assistance is needed.
These are different from the roof light used to show whether a taxi is available for passengers. New York’s older roof-light system used separate illuminated markings for availability and duty status; the city simplified that arrangement in the early 2010s. The amber trouble lights remain a separate warning system rather than a way to indicate that a cab is vacant.
The wording can cause confusion because emergency responders include several services. In this specific New York taxi context, the signal is associated with police, not mechanics, paramedics or firefighters. The equipment is especially useful when a driver faces a robbery, assault or other immediate threat and cannot safely make a conventional request for help.