Abstract: A method of detecting a slip of a driving wheel of an automotive vehicle is disclosed. According to this method, a vehicle acceleration is determined on signals used to control a power train of the vehicle, and a target vehicle speed, i.e., a vehicle speed which ought to be accomplished with the vehicle acceleration, is computed, a peripheral speed of the driving wheel is determined, and the occurrence of a slip is determined in response to a difference between the target vehicle speed and the peripheral speed.

Abstract: Operational parameters such as engine rotational speed, torque output and fuel consumption are continuously monitored and an engine control schedule updated using filtered data so as to calibrate same against the current or actual state of the engine and therefore compensate not only for the effect of wear which occurs with the passing of time, but also the unit to unit difference which is inherently present in production engines.

Abstract: A computer having a main read only memory is so arranged that a portion of the information stored in the main read only memory can be changed, if desired, without changing the entire main memory. Information to be substituted for a portion of the main information contained in the main memory is stored in a correction memory, which is incorporated in the computer when required. The CPU is arranged to fetch and use instructions or data alternatively from the main memory or the correction memory in such a manner that a predetermined portion of the main information is replaced by the substitute information. In one embodiment, data is stored in the correction memory for designating which portion is to be replaced and the CPU selects either memory depending upon this data. In another embodiment, one or more comparators are used for comparing the value on an address bus with addresses for designating the start and the end of the portion to be replaced.

Abstract: A method and apparatus for controlling fuel to be supplied from a motor-driven fuel pump to fuel injection valves of a fuel injected engine, the time period during which the fuel injection valves are kept open and the power duty cycle for driving the fuel pump motor are both calculated by a microcomputer responsive to one or more engine operating conditions. Reduced power consumption of the pump motor is achieved, thus resulting in reduction in the load applied to the battery and therefore improving the fuel consumption rate. The apparatus comprises an input unit, an injector drive unit, and a pump drive unit in addition to the microcomputer, and includes circuits for converting both the time period and the power duty cycle according to the battery voltage and the degree of engine acceleration.

Abstract: An electronic engine control apparatus includes a digital computer which receives sensor signals indicative of various engine operating parameters and calculates corresponding settings of actuators used to control the energy conversion process of an internal combustion engine. The apparatus has a memory for storing and holding data independently of an ignition switch being turned off. The apparatus includes a data input for inputting data specifying a function to be performed, a memory location and a numeral. The computer is programmed to perform the function using the numeral and the memory location. The function to be performed may include modifying data in the memory location in accordance with the numeral.

Abstract: An electronic control system for an automotive vehicle including an engine control system for controlling the engine operation using a microcomputer and a vehicle driving information system for preparing and displaying various driving information using another microcomputer, wherein a back up program is assembled into each microcomputer for backing up at least the critical jobs of the partner microcomputer when the partner fails so as to ensure continuing, safe operation of the vehicle.

Abstract: In an engine speed sensing device, angle pulses produced when the crankshaft rotates through a predetermined angle are counted by a counter for a predetermined interval. The count of angle pulses is read into a central processing unit of a digital computer at the end of each set time interval in response to a control signal which both updates the angle pulse count and signals the processing unit to read the count.

Abstract: A fail-safe system for an engine control system is capable of performing a fail-safe operation when a crank angle sensor fails. When the crank angle sensor malfunctions, at least one of a crank reference signal and a crank position signal will be absent. The fail-safe system prevents the engine from stalling even when one of the crank reference signal and the crank position signal is absent. The fail-safe operation will be carried out when the absence of the crank reference signal and/or the crank position signal is detected. In the fail-safe operation, a fail-safe signal is produced for controlling engine operation as a replacement for an engine control signal from the engine control system under normal conditions. The signal value of the fail-safe signal may be variable in accordance with an engine operating condition derived from an engine control parameter other than the crank angle sensor signals.

Abstract: A fuel injection control system is disclosed which generates a fuel-injection command pulse signal having a constant repetition rate and a pulse width calculated from an algebraic relationship defining fuel-injection pulse-width as a function of engine air flow. The system can eliminate the need for engine-speed calculations and increase system reliability.

Abstract: A method of confirming that a memory other than a main memory is incorporated into a computer system, e.g., a microcomputer via a bus comprising the steps of predefining at least one bit line of a parallel bus provided between a receptacle for the memory device and a central processing unit (CPU) so as to impose a logical value, i.e., a "0" or a "1", on the data bus line, that value being the opposite of the predetermined logical value of data stored in a predetermined address of the memory device; operating the CPU to attempt to access the predetermined address of the memory device to read the data stored in the predetermined address of the memory device; and checking to see whether the data read in the central processing unit via the data bus line indicates a value or equal to the predefined value, thus determining that the memory device has or has not been incorporated into the computer. In another method, the bit line is connected via a resistor to an output line.

Abstract: A feedback air fuel ratio control system or method for a multi-cylinder engine is arranged not only to control the average value of the air fuel ratios among the cylinders but also to control the individual air fuel ratio of the individual cylinders so as to level the cylinder to cylinder air fuel distribution. This is done, for example, by directly detecting which cylinder is a source of the air fuel deviation by examining the oxygen sensor signal fluctuation in relation of time and individually regulating a fuel injector for that cylinder. In the case of an engine with a carburetor, the carburetor is controlled in relation with time in accordance with the sequence of the intake periods of the individual cylinders to control the individual air fuel ratio.

Abstract: A method and system for correcting engine ignition timing without the use of any pressure sensor or vibration sensor and depending upon engine knocking is disclosed. The presence or absence of knocking is determined by reference to the rate of change of engine speed. This method is based on the fact that engine speed changes abruptly when engine knocking occurs, as compared with the normal engine condition, because of abrupt changes in pressure within the cylinders. The system of the present invention comprises an crankshaft angle sensor to generate a crankshaft angle pulse signal, a period measuring means to output an interrupt request signal and to determine the presence or absence of engine knocking, a microcomputer, and an ignition signal generator for outputting an ignition signal in accordance with an ignition timing signal and a dwell angle signal.

Abstract: A fault diagnostic system is arranged to detect faults in a fuel system of an engine with an electronic fuel injection system by monitoring the quantities of fuel consumed during a time interval. To do this, the consumption quantity of fuel is determined from a decrease of the residual quantity of fuel remaining in a fuel tank which is detected by a fuel gauge. On the other hand, the fuel injection quantity is determined independently by summing the length of the injector open time of each injection. Then, the fuel consumption quantity and the fuel injection quantity during the same time interval are compared. If the difference therebetween is larger than a predetermined permissible range, it is decided that there is some fault somewhere in the fuel system, and an indication signals is produced.

Abstract: A digital control system for an internal combustion engine uses a two stage register. The register is used to store digital data representative of sensed engine operating conditions and to feed such data to a programmable digital computer for processing. Processing time is improved by reading only one register containing the most significant data bits of the stored data for engine parameters having a relatively narrow dynamic range and reading both registers, containing all data bits of the stored data for engine parameters having a relatively large dynamic range.

Abstract: A fuel injection control system for an internal combustion engine including a sensor unit for detecting at least one engine operating condition, at least one fuel injection valve for supplying fuel to the engine, and a regulator for maintaining the pressure across the fuel injection valve at one of a set of values. A control unit is provided for controlling the fuel injection valve and the regulator in response to the output signal of the sensor unit in such a way as to change the regulated value of the pressure according to the engine operating conditions while keeping the amount of fuel injected constant.

Abstract: An electronic engine control system has a pressure sensor communicating both to the intake manifold and the ambient air via a valve means selectively introducing either the intake vacuum or the ambient air into the pressure sensor. The control system further includes a valve control means for controlling the operation of the valve means for selectively communicating the pressure sensor to the intake manifold and the ambient air. The valve control means is incorporated in a controller for determining the control value and adapted to produce a control signal to be supplied to the valve means in order to electrically control the valve motion.

Abstract: An ignition energy control method and system such that a high ignition energy is supplied to the spark plugs only while the engine is operating under an unstable condition. The unstable engine operating condition is determined by detecting the difference in the maximum engine speed within a predetermined crankshaft revolution angle or by detecting the low-frequency vibration generated by the engine. The ignition energy is controlled by calculating an appropriate pulse-width of an ignition signal or by changing a high voltage generating plasma within the cylinders. The ignition energy control system according to the present invention comprises a crankshaft angle sensor or a low-frequency vibration sensor, a calculating and storing means, and an ignition system including a plasma generating power supply where necessary.

Abstract: A fail-safe device in an electronic control system for an automotive vehicle comprises a monitoring device for detecting failure of the CPU and generating a signal indicative of error in the CPU, and a storage device for outputting data to replace the CPU output while the CPU is operative. Thus, the control system can work for controlling a vehicle control device even during CPU failure.

Abstract: Disclosed is a fuel supply control system for controlling fuel amount to be supplied to an internal combustion engine including a sensor means for detecting engine load condition and other control parameters and generating sensor signals, an arithmetic means for determining a basic pulse width of a pulse signal indicative of basic fuel amount to be supplied, a means for correcting the basic pulse width of the pulse signal corresponding to various control parameter respectively indicative of engine conditions such as engine coolant temperature and a means for distinguishing engine driving condition based on inputs one of which is sensor signal indicative of engine load condition and generating correction command indicative of correction coefficient. The correction command is applied to the correction means to effect the same to increase or decrease the pulse width of the pulse signal or shut off the fuel supply to the engine.

Abstract: An automatic control system for an automotive vehicle in use with a microcomputer has a checking system for checking an input unit, a ROM, a RAM and an output unit of the microcomputer. The checking system comprises a means which stores various checking programs to be executed for checking above-mentioned elements of the microcomputer. The checking system effectively operates to check the elements without causing expanding of duration of execution of the checking programs.