Abstract: A device (10) is disclosed for intercepting the input of a system (23) of an internal combustion engine (12) normally provided to a solenoid valve (22) for actuating a fan clutch (20). A pressure switch (24) is provided in the pressure line between the solenoid valve (22) and the fan clutch (20). The input is received by terminals (27, 28) and is passed on to a transistor (53) which turns on and allows current flow to the solenoid valve (22) during a first period of time. If a second transistor (48) turns on because the pressure switch (24) remains open as a set point is not sensed in the pressure line and does not discharge a time delay circuit formed by a combination of a resistor (44) and a capacitor (46), then the voltage of the gate of the first transistor (53) is pulled down to turn the transistor (53) off and interrupt the current flow to the solenoid valve (22).

Abstract: A device (10) is disclosed for intercepting the input of a system (23) of an internal combustion engine (12) normally provided to a solenoid valve (22) for actuating a fan clutch (20) when rotation of a fan (16) is desired. The input is received by terminals (42, 43) and is conditioned and passed on to a timer (96) and a controller (97). A vacuum switch (24) senses whether the fan (16) is rotating and provides a second input to the controller (97). In the event that an input is provided by the system (23) and the time delay signal has been provided by the timer (96) and also in the event that an input is provided by the system (23), the time delay has expired, and the second input is provided by the vacuum switch (24), the controller (97) provides an actuation output to terminals (71, 73) connected to the solenoid valve (22) by use of actuation provisions (98) to actuate the fan clutch (20).