Mercedes S-Class W-140

1991-1999 of release

Repair and car operation

Mercedes S-Class
+ Mercedes-Benz Cars of a class S (W-140)
+ Operation manual
- Routine maintenance
   Active system of the prevention of term of approach planned THAT (ASSYST)
   Schedule of routine maintenance
   General information on control
   Check of levels of liquids, control of leaks
   Check of a condition of tires and pressure in them, designation of tires and disks of wheels, rotation of wheels
   Replacement of impellent oil and oil filter
   Check of brake system
   Check of fuel system, replacement of the fuel filter
   Check of a condition and replacement of hoses of an impellent compartment, localization of leaks
   Check of a condition of ridge belts of a streaming drive of auxiliary units
   Check of functioning of system of cooling and frost resistance of cooling liquid, liquid replacement
   Check of a condition of system of production of the fulfilled gases
   Check of level of ATF, AT filter replacement
   Visual check of tightness of automatic transmission
   Check of a condition of components of a suspension bracket and steering
   Check of a condition of protective covers of power shafts
   Check of central air of air
   Greasing of limiters of doors and cylinders of locks
   Visual control of a seat belt and safety cushion block
   Check of operability of headlights and horn
   Condition check, adjustment and replacement of brushes of screen wipers
   Check of a condition of the battery, care of it and charging
   Replacement of the salonny filter
   Replacement of brake liquid
   Check and replacement of spark plugs, check of a condition of high-voltage wires (petrol models)
+ Engine
+ Systems of cooling, heating
+ Power supply system and release
+ engine Electric equipment
+ gear shifting Box
+ Avtomaticheckaya transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


Check of central air of air

Central air of air is under a high pressure. Do not try to weaken any connections or to remove system details without a preliminary discharge of system. The coolant should be removed from system in a specialized workshop (the type of a used coolant is given in Specifications). Even after a system discharge at performance of any operations with system use goggles.

In order that central air of air functioned regularly, it is necessary to perform the following operations regularly:

   a) Check a condition of a driving belt. At detection of excessive wear or damages it is necessary to replace a belt (see. Section Check of a condition of ridge belts of a streaming drive of auxiliary units);
   b) Check a condition of pipelines of system. Examine them in search of cracks, swellings and consolidations. Examine also shtutserny connections in search of traces of leaks. At detection of wear tracks, damages or leaks replace the damaged pipeline.
   c) Examine a surface of the heat exchanger located before a radiator of system of cooling. At detection of pollution of edges, insects, etc. clear a heat exchanger surface a special brush or the compressed air.

When using the compressed air use goggles!

   d) Be convinced that the drainage tube of the evaporator is not littered. At the switched-on conditioner from this tube should exude pure water. For check of purity of a tube enclose under the evaporator a sheet of paper and turn on the conditioner. After some period of time on a leaf there should be water traces.

Turn on the conditioner at least once a month (even in the winter). If not to use the conditioner long time, it can lead to an exit of consolidations out of operation.

Owing to complexity of system diagnostics and repair should be carried out at car repair shop.

The most probable cause of decrease in overall performance of system is the lack of a coolant. If you noticed sharp decrease in overall performance of system, check quantity of a coolant in system as follows.


1. Warm up the engine to working temperature.
2. As the switch choose the lowest temperature of submitted air. Include the highest speed of the fan. Open doors (that the system was not switched off after achievement of the demanded temperature in salon).
3. At turning on of the compressor its coupling should publish heard click, and the central part of the coupling to rotate. Touch an inlet and exhaust pipe of the compressor. One of them should be cold, another is hotter. If you do not feel a difference, the system is faulty. It can be caused as a lack of a coolant, and something by another. For elimination of malfunction address on HUNDRED.