a method of rationalizing a plurality of temperature sensors associated with a plurality of electrical systems of a vehicle includes : maintaining each of the respective electrical systems of the vehicle in a non - operational state for a predetermined period of time ; receiving a temperature reading from each of the plurality of temperature sensors following the predetermined period of time ; computing a master - reference temperature value from the plurality of received temperature readings ; determining a difference between each of the respectively received temperature readings and the computed master - reference temperature value ; comparing each determined difference to a threshold ; and providing an indicator if one or more of the determined differences exceeds the threshold .