Mercedes C-Class

W203 since 2000 of release

Repair and operation of the car

+ Mercedes-Benz cars of class C (W-203)
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling system and heating
+ Power supply system and release
+ Engine electric equipment
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
- Suspension bracket and steering
   + Suspension bracket of forward wheels
   + Suspension bracket of back wheels
   + Angles of installation of wheels of the car
   - Steering and safety cushions
      Steering and safety cushions - general information and security measures
      Security measures during the works with a safety cushion
      Removal and installation of the block of a safety cushion on a steering wheel
      Removal and installation of a steering wheel
      Removal and installation of a tip of steering draft
      Removal and installation of a protective cover of the steering mechanism
+ Body
+ Onboard electric equipment

Steering and safety cushions

Steering and safety cushions - general information and security measures


1 — the Steering column
2 — the Cardan hinge
3 — Gear and rack transfer of the steering mechanism
4 — the Rotary fist right
5 — Steering draft right
6 — the Protective cover right
7 — the Protective cover left
8 — Steering draft left

Rack steering mechanism

1a — the Case of the steering mechanism
1b — Rubber pillows of support
1e — Oil lines
1g — Protection covers with fixing collars
2 — Steering drafts
3 — the Cover with marking of the central position of the rack mechanism (shooter)
4 — the Case of a bladed lock and the operating plug
5b — the Socket of the right pressure chamber
5c — the Socket of the left pressure chamber
6 — the Compensator of a side play of a steering rack

Elements of the rack helmsman mechanism

1 — Gear and rack transfer of the steering mechanism
2 — the Protective cover right
3 — the Support lower
4 — the Lock level, for steering at a cross-piece
5 — M12 Bolt
6 — the Sealing ring *
7 — the Collar big *
8 — the Protective cover left *
9 — the Collar small *
10 — the Tip of steering draft
11 — the Nut, 55 Nanometers which is self-stopped surely replace with new
12 — M14 Nut
13 — Steering draft
14 — M8 Bolt
15 — the Steering column
16 — M8 Nut

*) Repair kit of a protective cover

Steering lath side play compensator

1 — the Compensator of a side play of a steering rack 2 — the Case of the steering mechanism

Hydraulic contour and elements of the steering car, sensitive to speed

4a — the Torsion bar
4b — the Leading gear wheel
4i — the Operating plug
4j — the Transfer lath
4k — the Bladed lock
A — Under pressure
B — Without pressure
I \Right executive cylinder (left turn)
II \Left executive cylinder (right turn)
Y10 — the Electromagnetic SPS valve
N47 — the Control unit of the antiprobuksovochny and stabilizing systems

Arrangement of the pump of the power steering (30)

Steering consists of a steering wheel, a steering column, the steering mechanism in the form of gear and rack transfer and drafts of the steering drive. The steering column transfers the movements of a steering wheel to the steering mechanism. The gear lath of the steering mechanism according to turn of a steering wheel moves to the right or to the left. Steering drafts transmit steering efforts to forward wheels through hinges and a rotary fist.

Gear and rack transfer of the steering mechanism is executed by bezzazorny and does not demand service. Within carrying out maintenance only control of protective covers and dustproof caps of tips of steering drafts is required.

The hydraulic booster providing decrease in the effort made for a steering wheel has steering of the car. The coefficient of strengthening increases at increase in speed of the movement. The hydraulic booster contains a hydraulic pump and the tank of working liquid. The hydraulic pump sucks in liquid from the tank and gives it under high pressure to the operating valve in the steering mechanism. The operating valve has mechanical communication with a steering spindle and directs liquid depending on turn of a steering wheel to the corresponding cavity of the working cylinder in the case of the steering mechanism. Here liquid influences the piston and thus supports management process. At the same time the piston squeezes out liquid from an opposite cavity of the working cylinder via the returnable pipeline in the liquid tank.

Functioning of the power steering (SPS), sensitive to speed

Electronic control the electromagnetic SPS Y10 valve is exercised of the N47 control unit depending on car speed.

At rotation of a steering wheel the leading gear wheel (4b) influences a lath (4j). The rotating ram (4k) by means of the torsion bar (4a) turns around the operating plug (4i) and rests against a lath (4j) that leads to change of relative position of managing directors of flutes. At the same time the oil stream under a pressure moves in the camera of the right or left executive cylinder (I or II), causing the axial shift of a lath (4j) in the corresponding direction. Oil from the unloaded executive cylinder is forced out and through open returnable flutes in the operating plug (4i) goes back to the tank of the steering pump.

Security measures

Production of welding and leveling works with elements of steering is not allowed. The self-stopped bolts and nuts, and also bolts and nuts having corrosion have to be replaced with new.

The moments of an inhaling of threaded connections have to be maintained surely.

In a steering wheel the safety cushion of the driver is located. The safety cushion represents the developing air bag which is filled with air at head-on collision of the car and thus protects the top part of a trunk and the driver's head. At head-on collision of the corresponding force the control unit sends a signal to a safety cushion fuse. As a result of explosion gas which inflates a pillow during several milliseconds is formed. This time is enough to damp movement of the top part of a trunk of the driver moving forward. Then within several seconds the safety cushion develops again since gases come out a pillow through the available openings.