Abstract: In an engine control unit, information showing the operation of the non-operation of the cooling fan, information showing the temperature of the coolant flowing out of the engine (1) or other parameters showing the engine operation are supplied. In the engine control unit, the temperature drop of the coolant brought about by the radiator on the basis of the operation of particularly the cooling fan is programmed to be read out from a map construction in the form of a table such that the temperature control is performed by predicting the change of the coolant. Therefore, it is possible to operate the engine at a high temperature not reaching a state of overheating such that fuel economy is attained while minimizing the generation of a poisonous exhaust gas.

Abstract: A cooling control system by which an internal combustion engine is prevented from overheating, and a fail-safe function exerts its effect. A butterfly valve 34b for regulating the flow of cooling water is rotated by a motor 31, a clutch mechanism 32, and a speed reduction mechanism 33, thereby cooling the engine to be at the most suitable temperature for driving. The aforesaid butterfly valve 34b is given momentum in a direction to open the valve 34b by a return spring 34e. For example, an angle sensor 34g for detecting the rotational angle of the butterfly valve 34b is included. In a computing unit, when it is determined that an abnormality occurs from the relationship between the data from an encode 34g and the temperature of the cooling water, the clutch mechanism 32 is released, and the butterfly valve 34b is automatically opened. Accordingly the engine is prevented form overheating.

Abstract: To provide a communications system to accurately detect when a mobile transceiver has entered an area where communication with a fixed transceiver is possible, and to start-up the internal circuitry of the mobile transceiver, a communications system transmits a start-up pilot signal of a prescribed period from a transponder mounted in a fixed station to a transponder mounted in a vehicle. In the transponder, the received signal upon being received by an antenna is detected in a detector and amplified in an amplifier. When this signal is greater than a reference voltage, a pulse is output from a level discriminator. This pulse signal is converted into a pulse of constant pulse width in a discriminator pulse generator and integrated in an integrator. When the integrated value exceeds a reference voltage, a start-up discriminator sends a drive signal to actuate the internal circuitry of the mobile transceiver.