The principal reason for implementing electronic computers in cars was to reduce exhaust emissions and facilitate repairs, if any. In the latter case the opinions are rather quite divided and ambiguous. The fact is that due to the use of such device in a car, any defect may be found much more faster and easier. Obviously, provided that a person who undertakes to make repairs has an adequate knowledge, experience and tools enabling data readout from the computer.
ECU / Engine control unit
This device is used mainly to control power transmission and engine operating parameters. Its role is to control the most important engine functions, beginning from ignition enabling engine start-up, through fuel injection to filters. By analysing information taken from many car subassemblies simultaneously, the engine computer select proper fuel doses and amounts of drawn air.
Obviously, to enable proper car operation, at first place a power supply, that is car’s electrical system is required. The device has been designed and made so that it is completely shockproof and resistant to various vibration during driving, and resistant to moisture. The car computer is most often a small flat box containing a processor, memory and appropriate software and a large number of various controllers responsible for functioning of many systems installed in a car. The engine control unit (ECU). As for each device of such type also for car computers it is advisable to be particularly careful when clearing defects and making repairs. This applies primarily to the need for use of welders and other devices that may cause overvoltages. To avoid damage to the computer it is better to disconnect it from the battery. Similarly, if the battery is to be recharged, it is required to disconnect it from the car’s electrical system.