A method for non-intrusive response time evaluation of a component , unit or system of a vehicle comprising at least one control unit and at least one sensor for measuring an actual operation value (A) of the component, unit, or system, the method comprising: - repeatedly obtaining (S1) information in the control unit regarding a set operation value (D) and an actual operation value (A) of the component, unit, or system; - repeatedly evaluating (S2) if a difference between the set operation value (D) and the actual operation value (A) is exceeding a predefined minimum difference (Δminrange); - if the difference is exceeding the predefined minimum difference, measuring (S3) a response time (Δt) from a time when the predefined minimum difference was exceeded until a time when a predefined change (Δmeasrange) of the actual value (A) is achieved, and/or measuring a change of the actual value (A) during a predefined response time, wherein the measuring of the response time and/or change only remains active if the set operation value (D) is continuously greater than the actual value (A) at positive measurement or continuously smaller than the actual value (A) at negative measurement, wherein positive measurement is defined as a situation when the actual operation value is increasing to reach the set operation value and wherein negative measurement is defined as a situation when the actual value is decreasing to reach the set operation value; and - if the measured response time is longer than the predefined response time and/or if the change of the actual value (A) has not achieved the predefined change (Δmeasrange) during the predefined response time, generating (S4) a fault signal indicative of a fault of the component, unit or system. - repeatedly obtaining (S1) information in the control unit regarding a set operation value (D) and an actual operation value (A) of the component, unit, or system; - repeatedly evaluating (S2) if a difference between the set operation value (D) and the actual operation value (A) is exceeding a predefined minimum difference (Δminrange); - if the difference is exceeding the predefined minimum difference, measuring (S3) a response time (Δt) from a time when the predefined minimum difference was exceeded until a time when a predefined change (Δmeasrange) of the actual value (A) is achieved, and/or measuring a change of the actual value (A) during a predefined response time, wherein the measuring of the response time and/or change only remains active if the set operation value (D) is continuously greater than the actual value (A) at positive measurement or continuously smaller than the actual value (A) at negative measurement, wherein positive measurement is defined as a situation when the actual operation value is increasing to reach the set operation value and wherein negative measurement is defined as a situation when the actual value is decreasing to reach the set operation value; and - if the measured response time is longer than the predefined response time and/or if the change of the actual value (A) has not achieved the predefined change (Δmeasrange) during the predefined response time, generating (S4) a fault signal indicative of a fault of the component, unit or system. <EOS>