A system having: a midplane having air flow channels therein; a disk drive mounted to a first side of the midplane; and a temperature sensors mounted to the midplane. The system includes a pair of electrical chassis connected to a second side of the midplane. A first one of the chassis has therein: a fan; and a fan controller for controlling speed of the fan in response to a temperature control signal. A second one of the chassis has therein: a microprocessor for: detecting temperature signals produced by the temperature sensors; comparing differences between the detected temperature signals; and selecting one of the detected temperature control signal from the compared differences as the temperature control signal. A faulty one of the temperature sensors is detected by: selecting one of the detected temperature control signal as the faulty one of the plurality of temperature sensors from the compared differences.