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.