since 1993 of release
Repair and car operation
+ Operation manual
+ Routine maintenance
+ engine Repair
+ Systems of cooling, heating
+ Power supply system and release
+ engine Electric equipment
+ Power shafts
+ Uniform hydraulic system
+ Brake system
+ Running gear and steering
+ Body and salon furnish
- Onboard electric equipment
Search of causes of failures of electric equipment
Safety locks and the relay - the general information
Removal and installation of switches
Replacement of lamps of external lighting and alarm devices
Replacement of lamps of internal lighting devices
Removal and installation of external lighting and alarm devices
Adjustment of optical axes of head headlights
Removal and installation of an instrument guard
Removal and installation of components of an instrument guard
Removal and installation of hours
Removal and lighter installation
Alarm system “do not forget to switch off lighting devices” - the general information
Removal and installation of a horn of a horn
Removal and installation of a driving cable of the speedometer/sensor of speed
Removal and installation of the lever of a screen wiper
Removal and installation of the electromotor and drafts of a drive of a cleaner of a windscreen
Removal and installation of the electromotor of a drive of a back screen wiper
Removal and installation of components of system of washing of glasses and lenses of head block headlights
Removal and radio tape recorder installation
Removal and installation of loudspeakers
Removal and installation of the aerial of a radio receiver
Anticreeping system - the general information
Safety cushion - the general information, precautionary measures and system deactivation
Removal and installation of components of a safety cushion
Diagnostics of systems of electronic control
+ electric equipment Schemes
Search of causes of failures of electric equipment
The typical electric contour consists of the consumer of the electric power (a working component), switches of management (keys), the relay, driving electromotors, safety locks, the fusible inserts/breakers of a chain concerning work of this component, and also connecting electroconducting, its contact plugs and sockets. For the purpose of simplification of performance of diagnostic procedures schemes of electric connections of various systems of electric equipment of the car are provided in the last section of this Chapter.
Before starting identification of causes of failure of the failed electric device, attentively study the corresponding electric circuit. Try as it is possible to imagine more clearly a principle of functioning of the components which are a part of this contour. The list of possible causes of failure can be minimized by a way of an exception of it unequivocally regularly functioning components concerning work of the checked chain. At simultaneous violation of functioning at once several components or contours, the most probable cause of refusal is failure of the general for these contours of a safety lock, or grounding violation.
More often refusals of electric equipment speak the elementary reasons, such as oxidation or weakening of fastening of terminal connections, failure of a safety lock or a fusible insert, failure of the relay, etc. Before starting search of internal defects of actually refused component, attentively check a condition of all safety locks concerning its functioning, contact sockets and electroconducting. For definition of the list of knots subject to check and terminal connections study the corresponding electric circuit (see. Removal and installation of components of a safety cushion).
It is necessary to carry to number of the main tools necessary by search of refusals of electric equipment:
Before starting actually performance of checks, attentively study the corresponding Schemes of electric equipment.
The simplest check of a chain which is carried out by twitching of various sites of electroconducting of the corresponding contour can be made for search of the reason of refusal having unstable character (refusals such usually appear connected with oxidation or weakening of fastening of terminal connections). As a result of such check it is possible to localize a defective piece of a chain. This check can be made in addition to any of listed below in the corresponding subsections.
Except the problems connected with violation of quality of electric connections, it is necessary to refer breaks and short circuit to number of the most probable and often meeting refusals of electric chains.
Chain break usually is defined by mechanical injury of tokoprovodny veins or a detachment of contact plugs that leads to disconnection of a contour and the tsirkulirovaniye termination in it an electric current. As a result of chain break its working component ceases to function, however the corresponding safety locks / fusible inserts do not fail.
Short circuit of its electroconducting is called as short circuit unforeseen a chain design. Thus the current starts to circulate on the shortest way, usually leaving on weight. Short circuits are connected with violation of integrity of isolation of electroconducting more often and without fail lead to failure of safety locks / fusible inserts of protection of a chain.
Search of breaks of a chain
Identification of the reasons of short circuit
Identification of violations of grounding
The negative plug of the battery is earthed on metal of the power unit called in "mass", the chassis and body elements of the car. Electric contours of the most part of electric equipment are constructed in such a manner that connecting electroconducting is used only for food giving to the consumer from the positive plug of the battery, return of a current to the battery is carried out on weight metal. It means that fixing elements of consumers form themselves a returnable part of a chain. In view of the aforesaid, weakening of fastening or development of corrosion of basic elements of a working component of a chain involves violation of serviceability of functioning of a contour from a full exit of the last out of operation, before partial refusal of various sites of a chain. In particular, as a result of weakening of fixture of devices brightness of a luminescence of lighting devices (can decrease in particular at the general grounding with other contour) or speed of rotation of the electromotor (for example, a drive of screen wipers or the fan of system of cooling). Thus refusal of one contour can cause violation of functioning of the another which outwardly in any way has not been connected with failed. Pay attention that on many cars certain knots are connected among themselves by special tires of grounding. Such tires are used when there is no direct contact of metal parts of blocks in view of the equipment of support elastic rubber pillows and plugs (as, for example, in support of fastening of the power unit to the car chassis).