Accessory control system for a vehicle

Abstract

An accessory control system for a vehicle which includes an engine, cooling fan driven by the engine and a selectively-operable, power-requiring accessory includes an electronic logic control module which is packaged within a logic control box and which is electrically connected between various sensors and various power-requiring accessories. The accessory control system further includes a first signal output line which is electrically connected between the logic control module and a power-requiring accessory, such as a combine unloader. Also connected to the logic control module is an engine temperature sensor which operates on a thermocouple principle and is connected to a relay within the logic control module. If the engine temperature is below a threshold level then the logic control module is able to disengage the cooling fan so as to make additional horsepower available for operation of the power-requiring accessory. The engine temperature sensor is electrically connected to the logic control module and the logic control module is further connected to the engaging clutch for the cooling fan. While the power-requiring accessory (unloader) is being used, if the engine temperature rises to the threshold level the corresponding signal will be sent to the logic control module which will reengage the cooling fan in order to protect the engine from overheating. By being able to divert horsepower from some accessory which is not required, another accessory can be used without any significant reduction in the engine horsepower which is used to drive the vehicle at a desired speed.