Audi A4

Since 1994 of release

Repair and car operation



Audi А4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ Exhaust system
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and channels всасывания
+ Injection system
+ Coupling
+ Transmission and the main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tyres
- The electrotechnical equipment
   The minus is connected to weight
   The help for orientation in the electrotechnical equipment of the car
   Wires
   Connections of wires
   The central switching knot
   Support of additional relays
   Box for electronics
   The relay and management blocks
   The switching relay
   H-contact of the relay of unloading
   The table of the relay and management blocks
   Safety locks
   The table of safety locks
   + Electric schemes
   + The accumulator
   + The generator
   + Starter
+ Ignition system
+ Illumination
+ The alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics



The help for orientation in the electrotechnical equipment of the car

Here lateral facing (2) in feet of the driver is unscrewed. By arrows fixing screws are shown. Under it there is a group of sockets (1).


Under lateral facing (1) from outside the passenger near to the driver too there is a group of sockets (2). By arrows fixing screws are shown.

On the right: the central switching knot (2) is in Audi A4 at the left under a control panel. «The 13-seater support of additional relays» (1) is above placed.

At the left: in drawing placing of nests of the central switching knot is shown.

Standard designations of plugs

Multi-coloured mixture of wires in the car is actually very well ordered, as many details of the electrotechnical equipment of the car are standardised. Figures on different knots and connecting elements of wires, and also in electric schemes on all German and on some foreign cars have the same value:

The plug 15 receives power supplies only at the included ignition from the ignition lock, thus along with ignition/injection system those consumers of the electric power which should receive a current only during car operation are supplied with a current. At wires to plugs 15 in most cases a cover of black colour, sometimes with a colour additional strip at certain consumers of a current.

The plug 30 receives a direct current from plus of the accumulator or from the generator at the working engine. At casual handling of tools it can lead to short circuits or cause a rain of sparks if the wire connected to a minus of the accumulator is not removed. These wires which are always energised, in most cases have red colour, sometimes with additional colour strips.

The plug 49 concerns system of faltering and emergency light signals.

Through the plug 53 pressure in system of clarification of glasses moves.

From the plug 56 the current on passing light headlights on yellow and yellow-black wires, and also on headlight headlights on white and white-black wires moves.

From the plug 58 the electric power on forward lay fires, and also on back lanterns and for licence plate illumination moves. Primary colour of a cover of wires grey, sometimes with an additional colour strip.

The plug 75 locks of ignition receives a current in the event that the ignition key is in position "is included".

The plug 31 – the weight plug by means of which the electric power consumer should be connected to weight to close an electric chain. At corresponding wires a cover of brown colour.

The designated electric sockets

In Audi A4 often separate wires are connected in the whole sheaves in a black cover that complicates search of a separate certain wire. In this case the help in orientation are provided многоштырьковые connections on which in this chapter the exact quantity of wires and their exact arrangement in electric schemes is described.