A sensor system for a vehicle, including a first sensor that detects at least one collision-relevant physical variable and outputs at least one corresponding first sensor signal, and at least one second sensor that, independently of the first sensor, detects at least one collision-relevant physical variable and outputs at least one corresponding second sensor signal, and an evaluation and control unit that receives the at least one first sensor signal and the at least one second sensor signal and evaluates them for the collision detection. A method is also described for monitoring a sensor. The evaluation and control unit uses at least one second comparison signal that is based on the at least one second sensor signal of the at least one second sensor to monitor the first sensor.