Mercedes M-Class W163

since 1997 of release

Repair and car operation

Mercedes W163
+ Mercedes-Benz Cars of a class M (W163)
+ Governing bodies and receptions of safe operation
+ Current leaving and service
+ Engine
+ Systems of cooling, heating and air conditioner
+ the Power supply system and production of the fulfilled gases
+ Systems of electric equipment of the engine
+ Manual box of gear shifting
- Автоматичеcкая transmission
   Search of malfunctions - the general information
   The general principles of functioning of system the transmission, operating signals
   Adjustment of a drive of switching of AT
   Removal and installation of the electrohydraulic control unit by switchings
   Removal and AT installation with the hydrotransformer
   Removal and installation of the selector module
   Removal and installation of a cable of blocking of the electronic switch of ignition (EIS)
+ Transmission line
+ Brake and auxiliary systems
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment

Автоматичеcкая transmission


General data
Type 5-step, automatic with electronic control by gear shifting
  • Models 163.113 (ML 270 of CDI)
  • Models 163.128/174/175 (ML 400 CDI, 55 AMG and 500)
  • Models 163.136 (ML 230)
  • Models 163.154 (ML 320)
  • Models 163.157 (ML 350)
  • Models 163.172 (ML 430)
Type and ATF volume See. Specifications to Head the Current leaving and service.
Codes of diagnostics of system of electronic control by automatic transmission see. Head of System of electric equipment of the engine.

Transfer relations and scheme of operation of AT 722.6 activators


Transfer relation













R (mode S)

- 3.10:1

R (mode W)

- 1.90:1

* switching Activators only in the kickdown mode
Codes of diagnostics of system of electronic control by the automatic transmission, taken by means of the OBD II scanner

Address to Specifications to the Head of System of electric equipment of the engine.

Efforts of a tightening of carving connections, Nanometer
Bolt of a head of draft of switching 12
Drain stopper of the pallet of a case of transmission 20
Bolts of fastening of the pallet to a case 8
Bolts of fastening of the thermofilter to a transmission case 8
Bolts of fastening of the electrohydraulic control unit to a transmission case 8
Bolts of fastening of assembly of the lever of the selector to the floor panel 6

At the moment of a troganiye from a place automatic transmission (AT) acts as ordinary coupling, and during movement performs work on gear shifting. On everything models considered in the real Management are established to series 722.6 AT.

The AT main hubs are: torque converter (hydrotransformer), planetary reducer and hydraulic or electronic control unit. Hydrodriving disk brakes and disk coupling are applied to transition to other transfer relation in a planetary reducer. The design of typical AT is shown on an illustration.

Design of typical AT

1 — the Entrance shaft
2 — the Electrohydraulic control unit switchings
3 — the Intermediate shaft
4 — the Blocking gear wheel of a parking
5 — the Target shaft
6 — Oil (ATF) the pump
7 — Gidrotransformator
8 — a reactor Shaft
9 — the Blocking coupling of the hydrotransformer
10 — Multidisk brake assembly В1

11 — Multidisk brake assembly В2
12 — Multidisk brake assembly В3
13 — Obgonnaya the F1 coupling
14 — Obgonnaya the F2 coupling
15 — Back planetary assembly of N
16 — Multidisk coupling К1
17 — Multidisk coupling К2
18 — Multidisk coupling К3
19 — the Central planetary assembly of M
20 — Forward planetary assembly of V

The torque converter on the functions corresponds to hydraulic coupling. Its task includes coupling implementation at a troganiye from a place and gear shifting.

The control system of transmission (known also as electronic system of synchronous switching) is the component of the modified control system of the engine established only on model from AT. The control system can work in a special emergency (safe) operation with a limited range of switchings in which passes at detection of any malfunction (to dashboards the special control lamp (is activated see. Head Governing bodies and receptions of safe operation). Switching in emergency operation allows to drive away the car under the own steam on car repair shop for performance of detailed diagnostics and necessary regenerative repair. On the basis of the analysis of the data arriving from various information sensors (not necessarily directly related to functioning actually transmissions), the module of management chooses as transmission (TCM) optimum from the point of view of profitability, smoothness of switchings and so forth a mode of functioning of AT. At the certain provision of a butterfly valve of TCM can give out command for the blocking of the hydrotransformer leading to restriction of switchings of AT by a range only of the 4th and 5th transfers that promotes considerable reduction of fuel consumption.

The unique procedure of service of AT which performance should be made on a regular basis, check of level of the working liquid (ATF) which order of performance is stated in Head the Current leaving and service is. Need for regular replacement of ATF is absent.

Near a radiator of system of cooling of the engine ATF cooler is established.

On the basis of the data arriving from gas traditionally established under a pedal of the sensor switch of activation of the mode kickdown, TCM carries out transmission switching on adjacent being used at the moment transfer at complete squeezing of a pedal that allows to raise essentially dynamic characteristics of the car, for example during overtaking commission.

There are some operating modes of transmission, each of which can be involved after moving of the selector to one of the following provisions: «P», «R», «N», «D», «1», «2», «3», «4» (address to Head Governing bodies and receptions of safe operation). Since 01.09.99 on all models selector modules with function of a consecutive choice of ranges of a mode of movement "D" (1, 2, 3 and 4) when transfer of AT to a mode of restriction of ranges of switchings (4, 3, 2 and 1) is carried out by lateral otzhimaniye of the lever (D +/D-) (see started to be established electronic. Section Start of motion and gear shifting).

Thanks to use of the special N/R sensor switch start of the engine can be carried out only when the lever of the AT selector is in the situation "R" or "N" that allows to prevent a casual troganiye of the car in start attempt.

In the present Chapter the general procedures of service AT lying within qualification of the average amateur mechanic are considered only most. More detailed information on a design, principles of functioning and service of AT of a series 722.6 can be found in the Managements No. 179 («Automatic transmissions of modern cars») and No. 187 («S-class W-203 Mercedes») ARUS publishing houses.