A system for detecting a disruption in a communication system of a vehicle, the system comprising: i) a vehicle bus; and ii) an electronic processor (205, 300) configured to, a) receive a message from the vehicle bus, the message having a format and a plurality of signals, b) test (305; 400, 402, 405, 410, 420, 415) the message by detecting an anomaly in a bus identifier, c) test (315, 325, 330; 502, 505, 510, 520, 515; 602, 605, 610, 620, 615; 702, 705, 710, 720, 715) the message by detecting an anomaly in the format of the message, d) test (335; 802, 805, 810, 815, 820, 825, 830, 840, 835) the message by detecting an anomaly in a time the message is received, e) test (340; 902, 910, 915, 925, 930, 840, 945, 955, 960) the message by detecting an anomaly in a signal parameter of a signal of the plurality of signals, and f) generate an error (515; 615; 715; 835; 825; 915, 930, 945, 960) when the anomaly in the format of the message, the anomaly in the time the message is received, or the anomaly in the signal parameter is detected; the system being characterized in that: g1) a further test compares, to a predetermined threshold, an amount the signal has changed from the beginning of a predetermined time period to the end of the predetermined time period, and if the value of the signal changes by more than the predetermined threshold in the predetermined time period, the electronic processor generates the error; or g2) a further test checks if fluctuations of the signal value of a signal within a predetermined time period are greater than a predetermined amount, wherein the fluctuations of the signal value are the absolute value of the sum of delta values of the signal over the predetermined period of time, and if the value of the signal fluctuates by more than the predetermined amount in the predetermined time period, the electronic processor generates the error. i) a vehicle bus; and ii) an electronic processor (205, 300) configured to, a) receive a message from the vehicle bus, the message having a format and a plurality of signals, b) test (305; 400, 402, 405, 410, 420, 415) the message by detecting an anomaly in a bus identifier, c) test (315, 325, 330; 502, 505, 510, 520, 515; 602, 605, 610, 620, 615; 702, 705, 710, 720, 715) the message by detecting an anomaly in the format of the message, d) test (335; 802, 805, 810, 815, 820, 825, 830, 840, 835) the message by detecting an anomaly in a time the message is received, e) test (340; 902, 910, 915, 925, 930, 840, 945, 955, 960) the message by detecting an anomaly in a signal parameter of a signal of the plurality of signals, and f) generate an error (515; 615; 715; 835; 825; 915, 930, 945, 960) when the anomaly in the format of the message, the anomaly in the time the message is received, or the anomaly in the signal parameter is detected; a) receive a message from the vehicle bus, the message having a format and a plurality of signals, b) test (305; 400, 402, 405, 410, 420, 415) the message by detecting an anomaly in a bus identifier, c) test (315, 325, 330; 502, 505, 510, 520, 515; 602, 605, 610, 620, 615; 702, 705, 710, 720, 715) the message by detecting an anomaly in the format of the message, d) test (335; 802, 805, 810, 815, 820, 825, 830, 840, 835) the message by detecting an anomaly in a time the message is received, e) test (340; 902, 910, 915, 925, 930, 840, 945, 955, 960) the message by detecting an anomaly in a signal parameter of a signal of the plurality of signals, and f) generate an error (515; 615; 715; 835; 825; 915, 930, 945, 960) when the anomaly in the format of the message, the anomaly in the time the message is received, or the anomaly in the signal parameter is detected; g1) a further test compares, to a predetermined threshold, an amount the signal has changed from the beginning of a predetermined time period to the end of the predetermined time period, and if the value of the signal changes by more than the predetermined threshold in the predetermined time period, the electronic processor generates the error; or g2) a further test checks if fluctuations of the signal value of a signal within a predetermined time period are greater than a predetermined amount, wherein the fluctuations of the signal value are the absolute value of the sum of delta values of the signal over the predetermined period of time, and if the value of the signal fluctuates by more than the predetermined amount in the predetermined time period, the electronic processor generates the error.