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>> The relay - the general information and check of serviceability of functioning
The relay - the general information and check of serviceability of functioning
The general information
For giving of power supplies or a management signal on many of electric power consumers in the car (such as components of system of injection of fuel, a horn, a starter, the fan (cooling systems, antifog headlights and so forth) are used the relay. Actually, the relay represents the electric key providing short circuit ВВ of a contour on НВ to a signal. The relay exit out of operation invariably involves refusal of functioning of the corresponding consumer. Two main relays (the fuel pump and ignition) are located in the main assembly block established in an impellent compartment, other "are scattered" on the car. The description of check of serviceability of functioning of the relay is resulted more low. The failed relays are subject to replacement.
Principle of functioning of the relay of various type
Correctness of connection of the relay always can be defined under schemes of the electric connections resulted in the Schemes of electric connections of the present Management.
Usually the management contour always is connected to two of contact plugs of the relay. At giving on these plugs NV of pressure the current starts to circulate on a winding of management of the relay therefore there is a short circuit of the big contacts of a working contour of the consumer of the electric power. Other plugs are plugs working (ВВ) a contour and become isolated among themselves at food giving on a management contour.
For the purpose of simplification of identification of plugs of the relay explanatory marks are usually put on its case with the image of the scheme of connection of keys. If similar marks are absent, it is necessary to address to schemes of electric connections (Schemes of electric connections see).
- For check connect an ohmmeter between two plugs VV of a contour of the relay, - in the relay of normally opened type conductivity should be absent. Now connect the wire-crosspiece equipped with a safety lock between one of plugs of management of the relay and the positive plug of the battery (In +). By means of other wire-crosspiece earth the second plug of management, - the relay should publish click after which the ohmmeter will fix conductivity presence (the relay of normally opened type). Some relays demand obligatory observance of polarity of connection.
- At negative result of check replace the relay.