Mercedes S-Class W-220

since 1998 release

Repair and operation of the car



Mercedes W220
+ Mercedes-Benz cars of the class S (W220)
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling system and heating
+ Power supply system and release
- Engine electric equipment
   - System of ignition and engine management
      Basic elements of system of microprocessor management
      Checks of a control system of ignition and injection
      Search of malfunctions - the general information and preliminary checks
      Check and adjustment of a corner of an advancing of ignition
      Spark plugs
      Self-diagnostics of systems of electronic control of the second generation of OBD II
      The controller of interface of the personal computer to onboard system of self-diagnostics of OBD II under protocols of the SAE standards (PWM and VPW) and ISO 9141-2
      Application of an oscillograph for observation of signals in chains of control systems
      Digital tire of data of CAN
   + Systems of a charge and start
+ Automatic transmission
+ Power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schemes of electric equipment








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Self-diagnostics of systems of electronic control of the second generation of OBD II

Connection of a multimeter to sockets of the control unit of the engine by means of an auxiliary splitter

001 — ECM Sockets
003 — the Digital multimeter
050 — a 126-contact splitter
108 — the Test cable
N3/10 — the Control unit of the engine (ME-SFI)

A-F — Sockets
II1/63 — splitter Sockets
III63/126 — splitter Sockets
At a rassoyedineniye of sockets on ECM the central socket (D) is installed by the last.
Important: The socket with red marking is not required now as the corresponding function is not provided in ECM.


Several diagnostic devices making monitoring of separate parameters of systems of decrease in toxicity and fixing the revealed refusals in memory of the onboard processor in the form of individual codes of malfunctions are a part of the OBD system. The system makes also check of sensors and actuation mechanisms, controls vehicle service cycles, provides a possibility of storing even of the failures which are quickly arising in the course of work and cleaning of the block of memory.

All models described in the present manual are equipped with system of onboard diagnostics (OBD II). A basic element of system is the onboard processor more often called by the electronic module of management (ESM), or the module of management of functioning of the power unit (RSM). RSM is a brain of a control system of the engine. Basic data arrive on the module from various information sensors and others electronic a component (switches, the relay, etc.). On the basis of the analysis of the data arriving from information sensors, and according to the basic parameters put in the processor memory, RSM develops commands for operation of various operating relays and actuation mechanisms, carrying out thereby adjustment of working parameters of the engine, and providing maximum efficiency of its return at the minimum fuel consumption. Data read-out of the processor memory of OBD-II is made by means of the special scanner connected to the 16-contact diagnostic socket of reading of the database (DLC) located in interior of the car.

In principle, reading of the codes of malfunctions which are written down in memory of system of self-diagnostics perhaps, on some models, by means of a lamp "Check the engine" or by means of an auxiliary light-emitting diode, and also by the codes highlighted on the display automatic by Quarter.


Data on diagnostic units

Check of serviceability of functioning a component of systems of injection and decrease in toxicity of the fulfilled gases is made by means of the universal digital measuring instrument (multimeter). Use of the digital measuring instrument is preferable for several reasons. First, on analog devices it is rather difficult (sometimes, it is impossible), to define result of the indication to within the 100-th and thousand shares while at inspection of the contours including electronic components in the structure, such accuracy is of particular importance. The second, not less important, the fact that the internal contour of a digital multimeter, has rather high impedance is the reason (internal resistance of the device makes 10 megohms). As the voltmeter is connected to the checked chain in parallel, the accuracy of measurement of subjects is higher, than smaller current will pass through actually device. This factor is not essential at measurement of rather high values of tension (9 ÷ 12 V), however becomes defining at diagnostics of the elements giving low-voltage signals, such as, for example, l-probe where it is about measurement of shares of volt.

Parallel observation of parameters of signals, resistance and tension in all chains of management is possible by means of the splitter included consistently in the socket of the control unit of the engine. At the same time on the switched-off, working engine or during the movement of the car, measurement of parameters of signals on splitter plugs is performed from what the conclusion about possible defects is drawn.

Special diagnostic scanners or testers with a certain cartridge (if it is provided), a universal cable and the socket can be used to diagnostics of electronic systems of the engine, automatic transmission, ABS, SRS and other. Besides, it is possible to use the expensive specialized automobile diagnostic computer which is specially developed for full diagnostics of the majority of systems of modern cars to this purpose (for example, ADC2000 of Launch HiTech). Also, it is possible to use scanners and specialized diagnostic analyzers to this purpose, for example FDS 2000, Bosch FSA 560 (www.bosch.de), KTS 500 (0 684 400 500) or the ordinary personal computer with the special adapter, a cable (for example, a set 1 687 001 439) and the installed program OBD II browser.

Some scanners, besides usual operations of diagnostics, allow to print out, at connection with the personal computer, the schematic diagrams of electric equipment which are stored in memory of the control unit (if are put), to program anticreeping system, to observe signals in car chains in real time.

You can also download the free version of a browser of OBD II for diagnostics of your car from our website arus.spb.ru

Diagnostics of electronic control systems of the engine, injection and ignition, automatic conditioner of air and ABS/ASR/ETS/ESP

Arrangement of the 16-contact diagnostic socket if it is established

The 16-contact diagnostic socket of system of onboard diagnostics of OBD II (on the USA models)


conclusion No.

Appointment

1
2
3
Signal of TNA (gasoline); TD (diesel)
4
Connection with the case, C. 31
5
The case - an alarm conclusion, C. 31
6
Tire of data of CAN high level (salon)
7
Electronics of the engine (ME)
8
Food, C. 87
9
Traction control system (ETS/ESP)
10
11
Control unit of transmission (ETC)
12
The activity module (AAM – All Activity Module)
13
Security systems
14
Tire of data of CAN. Low level (salon)
15
IC control panel
16
Plus batteries through a safety lock. Energized at any position of the lock of ignition, C. 30

The 38-contact diagnostic socket for extraction of the blinking codes (if it is established)

Connect wires according to the scheme. The wire shown by a dash line is connected to a certain conclusion for diagnostics of a certain system (address the list of purpose of contacts):

  • to a conclusion 4 for diagnostics of system of injection;
  • to a conclusion 8 for diagnostics of the main unit;
  • to a conclusion 17 for diagnostics of system of ignition;
  • to a conclusion 19 for check of the block of diagnostics.
Purpose of contacts of the 38-contact diagnostic socket



1

Weight, contour 31 (W12, W15, electronic grounding)

2

Tension, contour 87

3

Tension, contour 30

4

EDS
System of electronic injection (diesel engines)

DFI
Injection of fuel with electronic distribution (diesel engines)

IFI
Consecutive electronic injection of fuel (diesel models)

HFM-SFI
System of the consecutive distributed injection/ignition HFM (engines 104)

LH-SFI
System of the consecutive distributed LH injection (engines 104, 119, 120 [the rights.])

ME-SFI
System of the consecutive distributed ME injection (engines 119, 120 [the rights.])

5

LH-SFI
System of the consecutive distributed LH injection (engines 120 [a lion.])

ME-SFI
System of the consecutive distributed ME injection (engines 120 [a lion.])

6

ABS
System of anti-blocking of brakes

ETS
Electronic traction control system

ASR
Adjustment of pro-slipping at acceleration

ESP
Program of electronic stabilization

7

EA
Electronic acceleration

CC/ISC
Control system of speed/stabilization of turns of idling.

8

BM
Basic module.

BAS
Amplifier of emergency brake application.

9

ASD
Automatic blocking of differential.

10

UTS
Electronic control by transmission.

11

ADS
Adaptive system of depreciation.

12

SPS
System of hydrostrengthening of a wheel, sensitive to car speed.

13

TNA signal (petrol models), LH-SFI engines.

TN signal (petrol models), HFM (ME) engines - SFI.

14

Signal, information on porosity, engines 119, 120 LH-SFI (rights.).

15

Signal, information on porosity, engines 120 LH-SFI (lion.).

IC

Combination of devices.

16

A/C
Air conditioning system.

17

DI
System of ignition with the distributor, engines 104, 119 and 120 (the rights.)

TD signal (temporary division) (diesel models)

TN signal, LH-SFI engines.

18

DI
System of ignition with the distributor, LH-SFI engines.

19

DM
Diagnostic module.

20

PSE
Pneumatic equipment.

21

CF
Comfort.

23

ATA
Anticreeping alarm system.

24-27

Are not used.

28

PTS
Parctronic system.

29

It is not used.

30

AB
Safety pillows / натяжители ETR (SRS) belts

31

RCL
Remote control of the uniform lock.

32-33

Are not used.

34

CNS
Communication system and navigation.

35-38

It is not used

Reading and removal of the blinking codes

Reading of codes is made by means of the simple scheme from the push-button switch and a light-emitting diode. Depending on type of the diagnostic socket and the system subjected to diagnostics, connection is made according to presented on illustrations.

 PERFORMANCE ORDER

1. Connect the scheme according to an illustration.
2. Include ignition.
3. Press and hold the switch button during 2-4 sec. and release it. In 2 sec. the light-emitting diode will give a code which value is equal to the number of flashes. Duration of flash is 0.5 sec., an interval of 1 sec. Identify a code on interpretation. For reading of the following code press the button again. For deleting of this code press the button and hold it during 6-8 sec. Besides, on some models, deleting of codes in memory is possible at shutdown of the negative plug of the rechargeable battery.
4. Switch off ignition and disconnect the scheme for check.

Diagnostics of electronic system of the automatic air conditioner (AC)

Diagnostic codes besides the special scanner can be schitana from the display of the Quarter control unit. Codes of malfunctions remain even at shutdown of the rechargeable battery.

Reading of codes

Include ignition;
Transfer handles of the choice of temperature to provisions of HI left and LO right;

During 20 sec. after the translation of handles at the same time press and hold the REST and EC buttons during 5 sec.;

The light-emitting diode of the RECIRCULATION key will begin to blink and on the display OFF will appear;

Press the right AUTO button more than 1 sec. If malfunctions in memory are not recorded, in the left part of the display there will be E, and in the right FF. Otherwise in the left part Ebl, and in right - a malfunction code is displayed (address the list of the KV codes below);

For a conclusion of a code of the following malfunction press the AUTO button;

For deleting of codes after their full reading press the right and left AUTO buttons more than 2 sec. In the left part of the display d, in the right FF is displayed;

By pressing the right AUTO button there is a restoration of the erased codes (compare to the codes which are written down earlier);

After removal of codes in the left part of the display E, in the right FF is displayed;

Install the handle of the choice of temperature in normal situation;

Switch off ignition.