Audi A4, S4

Since 2000 of release

Repair and car operation



Audi A4, S4
+ Introduction
+ Controls and receptions of safe operation
+ Current leaving and service
+ The engine
+ Systems of cooling, heating and the air conditioner
+ Power supply systems, release and decrease in toxicity of the fulfilled gases
+ Systems of an electric equipment of the engine
+ Manual box of a gear change
- Automatic transmission
   Specifications
   Search of malfunctions - the general information
+ Coupling, power shafts and differential
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment



Automatic transmission

The car can be equipped by an automatic transmission or a box with бесступенчатым gear change Multitronic.

The box can be removed without engine removal. To remove a box it is necessary at its replacement or repair. It is not recommended to carry box out repairs in house conditions.

Management of transmission is in detail described in the Head Controls and receptions of safe operation.

Removal and installation procedures are similar to removal and installation РКПП, the description is resulted in Section Removal and check point installation.

Automatic transmission, in process трогания from a place, carries out function of ordinary coupling, and during movement performs work on a gear change.

The basic knots АТ are: the twisting moment converter, a planetary reducer and a hydraulic or electronic control system. To transition to another transfer the relation in a planetary reducer are applied гидроприводные disk brakes and disk coupling.

The twisting moment converter on the functions corresponds to hydraulic coupling. Its problem includes coupling realisation at трогании from a place and a gear change.

Management of switching is carried out by the electronic block. Thus the electronic block for correct management uses the various information which allows for each mode of movement of the car and depending on desire of the driver to choose the optimal transfer relation.

Switches of programs, as for example «Economy» or «Sport», are not required, since the management block automatically, on a movement mode, establishes switching points. At definition of points of switching resistance to movement, as for example, lifting or descent from mountain, towage of the trailer and head wind presence are considered also.

The control system can work in a special safe mode in which passes at detection of any malfunction. Thus transmission operating modes are limited, and the car can be delivered under the own steam to repair shop. At control system transition in a safe mode on a control panel the control lamp (address to the Head Controls and receptions of safe operation) lights up.

Analyzing the information arriving from various gauges (not only the gauges directly related to transmission), the control system chooses optimum from the point of view of profitability, smoothness of a course etc. a box operating mode. At certain position заслонки a throttle the control system can block the hydrotransformer in such a manner that the fourth and fifth transfers will join only. It reaches considerable decrease in consumption of fuel.

Unique regular procedure of service of a box is check of level of a working liquid (address to Section Check of level of oil of automatic transmission). Regularly to change трансмиссионную a liquid it is not necessary.

Near to a radiator of system of cooling the cooler трансмиссионной liquids is established.

There are some operating modes of transmission, each of which can be involved after moving of the selector to one of following positions: P, R, N, D, S (address to the Head Controls and receptions of safe operation).

The engine can be started only if the selector is in position Р or N. It is made to prevent car movement at start attempt (if the selector is established in one of other positions). Analyzing the information arriving from gauges, the control system resolves or forbids engine start. The locations of various relays are specified in the Head the Onboard electric equipment.

The selector 5-step АТ Tiptronic near to a path of positions of automatic switching has the second path of step-by-step (consecutive) switching. The sports steering wheel can be equipped by corresponding keys. Such switching is accepted in sports cars.

In the presence of box Tiptronic the driver can make compulsory switching on higher and lower transfers. In comparison with manual switching Tiptronic more комфортабельна also it is protected against erroneous management. So for example, switching on lower transfer is made only if turns thus do not leave for certain borders.

In the presence of malfunctions of entrance signals or electromagnetic valves switching on the emergency program is made. Simultaneously arisen malfunction registers in memory of malfunctions. The information from memory can be считана the special device.

Automatic transmission Multitronic with бесступенчатым a gear change

Бесступенчатая АТ Multitronic

Multitronic - бесступенчатая transmission CTV with smoothly changeable transfer relation which provides not only an effective utilisation of capacity of the engine, but also provides good dynamics and comfort of driving.

System Multitronic basic element is клиноцепной a variator. By means of a variator transfer relations between a mode трогания from a place and last transfer change smoothly. Thanks to it the engine, irrespective of a movement mode, мощностного or economic, works in an optimum mode corresponding to it. The variator consists of two conic pairs connected with each other by a lamellar chain. As in each pair disks the conic disk moves an electrohydraulic drive, working diameter of a chain and thereof the transfer relation smoothly changes. Besides, in Multitronic coupling cooled by oil which excludes not only typical lacks of the converter of a twisting moment is applied, but also gives the chance various variants трогания from a place. The variant gets out an electronic control system according to desire of the driver which is distinguished on character of moving of a pedal of gas. Besides, электронноуправляемое coupling realises a stable mode of creeping movement which is a comfort element. The electronic control system, besides, provides the identification of the driver and a state of environment and works with the dynamic program of regulation DRP. The specified program on character of moving of a pedal of gas defines, whether the driver in dynamical or in an economic mode wishes to move.

If the driver gives full gas (kik-daun), the electronic control system is switched at once to sports control mode and lowers transfer that provides necessary high number of turns of the engine. At a normal mode of movement the choice of the optimum transfer relation, and all its changes, unlike step switching АТ is made, are carried out smoothly, without jerks and is imperceptible. Electronics distinguishes also liftings and descents and compensates additional loading or increases the moment of braking by the engine.

In a mode of manual switching of 6 blocks of management of the fixed transfer relations (transfers) brought in memory can smoothly be switched by the lever of the selector or buttons on a steering wheel.