A comparing module receives first data regarding surroundings of a vehicle from a plurality of sensors in the vehicle, receives second data regarding the surroundings from the plurality of sensors after receiving the first data, compares the first data to the second data, and determines a first difference between the first data and the second data based on the comparison of the first data to the second data. A perception module generates a first set of perception results based on the first data, generates a second set of perception results based on the second data, and determines a second difference between the first data and the second data based on the first set of perception results and the second set of perception results. A diagnostics module determines whether one of the sensors or the perception module is faulty based on a combination of the first difference and the second difference.