Abstract: A vehicle treatment system includes at least one treatment device that is movable relative to a vehicle to be treated. The vehicle treatment system also includes a collision detection device for width monitoring of a maximum treatment area of the vehicle treatment system, which for monitoring a lateral boundary of the maximum treatment area has at least one first optical sensor and a control unit for evaluating output values of the first optical sensor. The detection area of the first optical sensor is aligned along a lateral boundary of the maximum treatment area of the vehicle treatment system and the treatment device in the direction of travel leading ahead by a specified distance. The control unit is set such that the control unit detects an imminent collision if a specified number of consecutive cycles is scanned with a covered event.