Electrical System Equipment & Instructions - Basic Knowledge - 210 Chassis: Component Locations Mercedes-Benz E-class W210/S210

Signal acquisition and actuation module, location/task/design/function - GF54.00-P-4101A

MODELS 202 as of 1.6.97, 208, 210.081 /281, 210 (except 210.081 /281) as of 1.3.97

Fuel pump relay location - GF54.15-P-4105-01F

Model 210 as of 3/97

Scheme 9

Instrument cluster (IC), location - GF54.30-P-0002-07A

Models 129, 140, 170, 202 Model 208 up to 31.7.99; model 210 up to 30.6.99

Scheme 10

Display instruments, location / task / function - GF54.30-P-2002A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

Inputs/outputs, location/task/function - GF54.30-P-2003A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

Control buttons, location/task - GF54.30-P-2004B

MODEL 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

The instrument cluster has various control buttons which are located on its left and right side.

1. The control buttons "+" and "-" (on the left side of the instrument cluster) are used to adjust the instrument illumination.
2. The control button "0" (on the left side of the instrument cluster) is used to reset the trip odometer. On model 210 as of 15.02.96, model 208 as of start of production and on other models as of 06.97 it also serves to operate the Active Service System (ASSYST).
3. The control buttons "h" and "m" (on the right side of the instrument cluster) are used to adjust the clock.
4. The control button "R" (on the right side of the instrument cluster) is used to reset the multi-function display (model 210 with multifunction display only). Active Service System (ASSYST) Operating instructions, resetting Engines 112, 113, 611 (engines with oil sensor) «GF00.20-P-0003-01A»(ref-271977-S30812626902007111500000) Model 210 as of 01.03.97 with engines 111, 602, 604, 605 and 606 As of 06.97 models 129, 140, 170, 202 except engines 112, 113, 611 (valid for engines with oil level switch) «GF00.20-P-0003-01B»(ref-271977-S13780031952007111500000) Electronic clock «GF54.30-P-3011A»(ref-271979-S37815044132007111500000) Purpose/function of terminal 58d, instrument display illumination «GF54.30-P-3008A»(ref-271979-S23053503622007111500000)

Instrument cluster illumination, location/function - GF54.30-P-2007B

MODEL 208 as of 1.8.99, 210 as of 1.7.99

Instrument cluster display illumination

The illumination of the instrument cluster (A1) switches on automatically when it is activated. It is activated when the driver's door is opened or the trip odometer reset button (A1s3) is pressed, for example.

The brightness of the illumination depends on

1. the brightness of the surroundings
2. the status of terminal 58K (side light On/Off)
3. the dimmer setting via the buttons for instrument and search illumination (bright) (dark) (A1s4, A1s5)

Brightness of display illumination when side light is on (terminal 58k On)

A distinction is to be made between two cases depending on the brightness of the surroundings which is measured by the phototransistor (p)

1. The phototransistor controls the brightness of the display above a defined threshold value of the brightness of the surroundings. The brightness of the display increases as the brightness of the surroundings increases, the dimmer setting does not have any influence.
2. Below the threshold value, the brightness of the display depends on the brightness of the surroundings and on the dimmer setting, with the higher value applying.

Brightness of display illumination when side light is off (terminal 58k Off)

The brightness of the display only depends on the brightness of the surroundings via the phototransistor. The brightness of the display can assume values from the threshold value up to maximum brightness. The dimmer setting does not have any influence.

When the brightness of the surroundings changes the brightness of the display only changes after approx. 3 seconds.

K1 and K2 line, location/purpose - GF54.30-P-2015A

MODEL 129, 140 as of 1.6.96, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

The K1 and K2 line connects the instrument cluster to the automatic air conditioning pushbutton control module.

The serial data line K1 supplies the air conditioning control module with the following information from the instrument cluster

1. Outside temperature
2. Engine coolant temperature
3. Driving speed of vehicle
4. Terminal 58d (illumination)
5. Engine speed
6. °F/°C conversion
7. Full load fuel shutoff (diesel-engined models)
8. Acceleration recognition (gasoline-engined model)

As of 02.97 also

1. Compressor emergency stop
2. Compressor shutoff when accelerating

The serial data line K2 supplies the air conditioning control module with the following information from the instrument cluster

1. Refrigerant pressure
2. Idle speed increase

HHT interface, location/task - GF54.30-P-2017A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

The instrument cluster has diagnostic capabilities. In other words, diagnosis is possible using a hand held test (HHT). The instrument cluster therefore has a line (K-line) which is connected to the data link connector (X11/4).

The instrument cluster, including the Active Service System (ASSYST), is tested with the HHT. The following functions can be selected

1. Control module version
2. Error memory
3. Actual valves
4. Controls
5. Manual transmission adaptation: -variant coding - settings

Instrument/display illumination, location/task/function - GF54.30-P-3008A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

Instrument illumination

The brightness of the instrument illumination can be adjusted with the adjusting button (b) on the instrument cluster (A1).

The dimmer circuit drawn in the illustration is used for this. It is supplied from terminal 58k and supplies a square-wave voltage to terminal 58d, whereby the on/off ratio of around 12 -100 % is adjustable.

The frequency of this voltage is approx. 64 Hz. Terminal 58d goes directly to the instrument illumination lamps and is available for external consumers up to a power of approx. 23 - 30 watts (depending on the model). Terminal 58d is short-circuit proof. The output voltage corresponds to battery voltage minus 0.5 V. On models 202,208 and 210 the on/off ratio depends on the brightness of the surroundings which is measured by the phototransistor (pt).

The instrument cluster transmits the on/off ratio as a CAN message. The information from terminal 58d is consequently available to all CAN participants.

Scheme 11

On/off ratio

The ratio of the times 1 to T is called the on/off ratio. T is the period and t 1 in which current can flow within a period.

The greater the on/off ratio, the greater is the average power (brightness of the lamps) which is delivered to the consumers (I). The voltage curve at terminal 58d is sketched for an on/off ratio of 40% and, for comparison, 90% in the figure.

The advantage of this type of brightness control compared with direct control of the lamp current with a potentiometer is the significantly higher efficiency, the extensive independence of load and the more compact construction.

Display illumination (models 129,140 up to 05.97 and 163, 168)

The display illumination has an actuated daytime/nighttime switchover via terminal 58k.

When the vehicle lights are switched off (daytime) the display illumination is switched to maximum brightness (to 88% on model 163).

When the vehicle lights are switched on (night-driving or day-driving light) the display illumination is dimmed.

The displays can be dimmed together with the instrument illumination but have a separate dimmer characteristic.

Display illumination (model 170)

When the vehicle lights are switched off (daytime) the brightness of the display is actuated with the daytime basic value. When the vehicle lights are switched on (night-driving or day-driving light) the brightness can be controlled between the limit values nighttime min and nighttime max.

Display illumination (models 129,140 as of 06.97 and 202, 208, 210)

A distinction is made between two cases depending on the brightness of the surroundings which is measured by a phototransistor (pt)

1. Above the brightness of the surroundings H nightime The phototransistor controls the brightness of the display. The brightness of the display increases as the brightness of the surroundings increases, the dimmer setting has no influence.
2. Below the brightness of the surroundings H nighttime the brightness of the display depends on the brightness of the surroundings and the dimmer setting, the higher value applying.

The new brightness stage is always adjusted only after approx. 3 seconds.

The brightness of the display is independent of the vehicle lights.

Display activation

The display is activated when terminal 15R is ON. It still

Model 129 only

The display is activated for approx. 30 seconds or the active phase is extended for a further 30 seconds by pressing the left

Display activation

1. The display is activated when terminal 15R is ON. It still remains active for approx. 30 seconds after terminal 15R is switched off.
2. The display is activated when terminal 15R is OFF: by switching on the vehicle lights (terminal 58k ON). The display still remains active for approx. 30 seconds after terminal 58k is switched off. The display is activated for approx. 30 seconds or the active phase is extended for a further 30 seconds by opening the driver's door (closing the door contact). On models 202 and 210 the display is also active for approx. 30 seconds after the driver's door is closed.

phase is extended for a further 30 seconds by pressing the left control button.

Models 140,163,168 and 170 only

The display is activated for approx. 30 seconds or the active phase is extended for a further 30 seconds by pressing one of the control buttons.

Models 202, 208 and 210 only

The display is activated for approx. 30 seconds or the active phase is extended for a further 30 seconds by pressing one of the control buttons "odometer reset", "clock setting in hours" or "clock setting in minutes"

Stepper motor, location/design/function - GF54.30-P-3009A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208, 210 as of 1.6.96, 215, 220

General

Stepper motors are motors which, like most electric motors, consist of a fixed stator and a moveable rotor. The rotary motion is not continuous, rather the rotor turns in steps, a certain angle at a time, for example 90°.

Design

The illustration shows the basic design of a stepper motor with 1 pole pair and 2 phases. The stator is made of magnetically soft iron and holds the windings. Opposite windings belong together and form a phase (in this case, a and b). The rotor consists of a permanent magnet. In the illustration the rotor has 1 pole pair.

Function

The rotor is turned by applying current through phase a or b (see illustration). The magnetism in the stator changes according to the polarization (I) of the phases.

Scheme 12

The rotor will turn so that its south pole (S) is at the north pole (N) of the stator and its north pole (N) is at the south pole (S) of the stator. The illustration shows a full rotation of the rotor. The rotor moves in steps of 90° from positions 1 through 4 and back to its starting position.

Unlike normal electric motors, the motor can stop in each of these positions with a certain holding torque. This type of motor is therefore particularly suitable for use as a servomotor for exact positioning.

The size of the steps can be reduced considerably by increasing the number of pole pairs and phases.

Theoretically, it is even possible to make the steps infinitely small with just a few poles and phases by using complicated electronic phase control (sine-cosine control).

Stepper motors (with sine-cosine control) are used, for example, for pointing instruments in the instrument cluster (A1).

Electronic clock, location/function - GF54.30-P-3011A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

General

A periodic process with a period of high accuracy is required to measure time (clock) (e.g. rotation of the earth, pendulum oscillation.)

Electronic clock

Accordingly an electrical clock signal of high frequency accuracy is required for an electronic clock. This clock signal is usually derived from the very constant mechanical oscillations of an oscillator crystal. A quartz (q) with a really high frequency (e.g. f 1 = 1 MHz) is normally used. This frequency is then adjusted down to the required frequency f 2 1 Hz or 1/60 Hz by an electronic frequency divider (t), i.e. one pulse is generated every second or minute. The display unit can be actuated by this pulse. A stepper motor (s) is used on clocks with a pointer and a liquid crystal display (I) on clocks with a digital display.

Scheme 13

With an additional circuit (b) the clock can be adjusted via control buttons.

In addition the time or a time/date pulse is also made available to other systems (e.g. trip computer, Active Service System (ASSYST), maintenance display).

Liquid crystal display (LCD), location/task/function - GF54.30-P-3015A

MODEL 129, 140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208, 210 as of 1.6.96, 215,220

Task

The liquid crystal displays (LCDs) can display numbers, letters and other symbols. They are therefore used as the output devices of electronic systems. They are increasingly used as a replacement for the conventional analog indicating instruments and indicator lamps.

Operating principle

The operating principle of the liquid crystal display is explained using a seven-segment display as an example (see illustration).

A spacer frame (d) which surrounds a thin layer of liquid crystal (e) is sandwiched between the glass plates (a) and (f). Transparent electrodes (segments) are attached to glass plate (a) in the shape of the desired characters.

The transparent counter-electrode (h) is on glass plate (f). If a voltage is applied between the contact (g) of the counter-electrode (h) and one or more contacts (b) of the segmented electrodes (c), the optical properties of the liquid crystal between the counter-electrode (h) and the energized electrodes (c) change. If the LCD is viewed in the direction of the arrow, the energized electrodes (c) appear dark and are thus visible. By actuating the appropriate electrodes (c) it is possible to display any number.

The liquid crystal display also has 2 polarization filters (i). These types of display have a better contrast and require a lower supply voltage (approx. 1.5 - 5 V).

Other characters can also be displayed if the appropriate electrode layout or shape is selected. Strip-type electrodes are usually used in the multifunction display (A1 p13). Here strip-type electrodes are attached to both of the glass plates (a) and (f). The strips on glass plate (a) are arranged vertically to the strips on glass plate (f). This arrangement allows individual dots (pixels) to be actuated. If different dots are actuated repeatedly in sequence at a sufficiently high speed, it is possible to produce almost any "image".

Photodiode and phototransistor, location / task / function - GF54.30-P-3016A

MODEL 202 as of 1.8.96, 208, 210 as of 1.6.96, 215, 220

Task

Photodiodes and phototransistors are used to measure light intensity so that electrical equipment can then be controlled using the measured signal.

In the instrument cluster (A1), a phototransistor is used in order to adapt the illumination or display brightness to the ambient brightness.

Semiconductors (general information)

Photodiodes are semiconductor elements. The conductivity of semiconductors (e.g. silicon) is between that of metals and nonconductors. The conductivity of semiconductors is largely dependent on

1. temperature
2. light exposure and
3. any contamination by foreign atoms.

Conductivity can therefore be influenced by deliberate contamination (doping). A distinction is made between two types of doping

1. N-doping The material is contaminated with foreign atoms which produce an excess of electrons. Since electrons have a negative charge, the term "N-type conduction" is used.
2. P-doping The material is contaminated with foreign atoms which produce a lack of electrons ("holes"). This results in positive charge carriers and the term "P-type conduction" is used.

Bringing together a P and N-doped layer produces a diode (block layer).

Owing to the displacement of electrons and holes, the conductivity of this array depends heavily on the polarity of the applied voltage.

The conductivity is very high when the N-material is connected to the negative pole and the P-material is connected to the positive pole (conducting direction).

If the polarity is different, the conductivity is very low (non-conducting direction).

Photodiode

In a diode, additional electrons and holes are produced when it is exposed to light. The conductivity of a diode connected in non-conducting direction therefore increases in proportion to the light intensity. Photodiodes are manufactured in such a way that this effect is especially pronounced.

Owing to the linear correlation between light intensity and conductivity, photodiodes are ideal for measuring purposes.

Phototransistor

A transistor is produced if 3 doped layers are combined in an NPN or PNP arrangement.

A transistor therefore has 3 contacts (emitter, base = control input, collector). Transistors can be used to amplify and switch electrical signals.

Here the NP or PN arrangement has the same effect as the photodiode. The correlation with respect to the conductivity of the transistor between the two outer layers (emitter and collector) is, however, greater owing to the transistor effect. The transistor therefore reacts even more sensitively to light than photodiodes.

Special phototransistors are usually manufactured without the base contact since no control input is required.

Quartz, location/task/function - GF54.30-P-3017A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208, 210 as of 1.6.96, 215, 220

Piezo-electric effect

A thin quartz plate (c) is coated on two opposing sides with a conductive material (a), (b) (see illustration). If a tensile or compressive load is applied to the array, an electrical voltage "U" is produced between the points (d) and (e). The polarity of the generated voltage depends on the direction of load (compression/tension).

Reversed piezo-electric effect

If, however, a voltage is applied to the points (d) and (e), the quartz plate increases or decreases in length.

Task

Mechanical vibrations can be converted into electrical oscillations using the piezo-electric effect. For example, for microphones, knock sensors, pressure sensors.

Electrical oscillations can be converted into mechanical vibrations or motion using the reversed piezo-electric effect: piezo-electric speakers, actuators.

Both effects are combined in the quartz resonator: If an AC voltage whose frequency is roughly equal to the mechanical resonant frequency (fundamental or harmonic component) of the quartz plate is applied to the points (d) and (e), the quartz is stimulated to generate resonant vibrations which stabilize the frequency of the electrical oscillations. For this reason, quartz resonators are often used where a high degree of frequency stability is required (e.g. in clock generators (oscillators) for electronic clocks and microprocessors).

Scheme 14

Electronic speedometer, location/task/function - GF54.30-P-4000A

MODEL 129,140 as of 1.6.96, 163, 168, 170, 202 as of 1.8.96, 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

Purpose

The electronic speedometer is used to display vehicle speed.

The display takes place via a display instrument with stepper motor.

Function

To determine the speed the instrument cluster computer uses the four wheel speed signals which it obtains from the traction systems control module via a CAN data bus. The vehicle speed is calculated by a comprehensive computing method. It is therefore only mentioned here briefly

The individual wheel speeds are compared and thus checked for plausibility. If significant differences in individual speed signals are recognized, the speed is determined from the speed of one of the front wheels.

If the speed signals differ significantly, it may be due to defective speed signals or cornering.

If the computer identifies by means of suitable comparisons (comparison of each side) that the vehicle is cornering, the speed is determined from the mean value of the front wheel speeds.

If the comparisons indicate one or more defective wheel speeds, the speed is determined from the highest wheel speed. This also applies if a fault indication is received instead of a wheel speed signal. In this case additionally an error bit is set.

If fault indications are received for all wheel speeds, the speed "0" is displayed (pointer of speed display on left end of scale).

Outside temperature display, location/function - GF54.30-P-4104A

MODEL 129

MODEL 140 as of 1.6.96

MODEL 170

MODEL 163, 202 with CODE (240a) Outside temperature display

MODEL 202 as of 1.8.96

MODEL 168

MODEL 208 up to 31.7.99, 210 as of 1.6.96 up to 30.6.99

To display the temperature, the outside temperature indicator A1p4 requires

1. the outside temperature
2. the speed signal
3. the engine running time and
4. the coolant temperature (model 129, and model 140 as of 1.6.96, model 170, model 202 as of 08/96 and model 163, model 168, model 210)

The outside temperature is determined by the outside temperature indicator temperature sensor B14. The temperature sensor is installed at the front left of the vehicle under the bumper and connected to the instrument cluster A1 via the 21 or 25-pin connector, coding part A terminal 1 and 2.

The speed signal, engine running time and engine temperature are determined internally by the instrument cluster A1.

Since the outside temperature display depends on the speed, engine running time and coolant temperature, high temperatures (influenced by the heat generated by the engine, for example) are not displayed when the vehicle is stationary or moving slowly.

Function, model 202 until 08/95

When the ignition is switched on and off and at speeds below approx. 20 km/h, the last temperature measured is stored and displayed.

If the measured outside temperature drops below the stored value, the current measured temperature is displayed.

If the outside temperature rises above the stored value, the current measured outside temperature is displayed only after the following delays

1. When the engine is not running, the current outside temperature is only displayed after 6 times the engine running time. For example, if the preceding running time was 5 minutes, the current temperature is not displayed until after 30 minutes. The maximum delay, however, is 1 hour. Up to 09.94
2. At vehicle speeds between 20-60 km/h, outside temperatures are displayed after a delay of approx. 5 min.
3. At vehicle speeds over 60 km/h, outside temperatures are displayed after a delay of approx. 2 minutes. As of 09.94
4. At vehicle speeds between 20-45 km/h, outside temperatures are displayed after a delay of approx. 3 min.
5. At vehicle speeds over 45 km/h, outside temperatures are displayed after a delay of approx. 1.5 min.

Function

Model 129, model 140 as of 1.6.96, model 170, model 202 as of 08/96, model 163, model 168, model 208 and model 210

1. When the ignition is turned on or off and with an engine temperature < 60°C the current temperature is always stored and displayed.
2. When the ignition is turned off and with an engine temperature < 60°C the temperature last measured is stored and displayed.
3. When the ignition is turned on and when an engine temperature < 60 (C The stored temperature is displayed.

If the measured outside temperature drops below the stored value, the current measured temperature is displayed.

If the outside temperature rises above the stored value, the current measured outside temperature is displayed only after the following delays

1. When the engine is not running, the current outside temperature is only displayed after 6 times the engine running time. For example, if the preceding running time was 5 minutes, the current temperature is not displayed until after 30 minutes. The maximum delay, however, is 1 hour.
2. At vehicle speeds between 20-45 km/h, outside temperatures are displayed after a delay of approx. 3 minutes.
3. At vehicle speeds above 45 km/h, outside temperatures are displayed after a delay of approx. 1.5 minutes.

Location of components for fanfare horns - GF54.35-P-0001-01A

Illustrated on model 210

Scheme 15

Scheme 16

Scheme 17

Parktronic system (PTS), location of components - GF54.65-P-0001-02B

Model 210 with code 220a Parktronic system (PTS)

Scheme 18

Scheme 19

PTS control unit, location - GF54.65-P-4100-01A

Shown on model 208

The Parktronic control unit (N62) is located on the control unit plate in the front passenger footwell

Scheme 20

PTS control module, location - GF54.65-P-4100-01AD

MODEL 210 up to 30.06.99 with CODE (220a) Parktronic system (PTS)

Location, model 210 up to 30.6.99

Scheme 21

PTS control unit, location / task - GF54.65-P-4100A

MODELS 140,163,168, 202, 208, 210, 215, 220 with CODE (220a) Parktronic System (PTS)

Illustrated on model 140

Scheme 22

PTS switch, location/task - GF54.65-P-4101A

MODELS 140,163,168, 202, 208, 210, 215, 220 with CODE (220a) Parktronic System (PTS)

Location in models 140,168, 202, 208, 210

Shown on model 208

Scheme 23

Sensors, location/task/function - GF54.65-P-4102A

MODELS 140,163,168, 202, 208, 210, 215, 220 with CODE (220a) Parktronic System (PTS)

Scheme 24

Shown on model 220 up to 30.06.02

Warning indicator, location - GF54.65-P-4104-02A

Models 202, 208, 210 up to 30.6.99, 215, 220 with code (220a) Parktronic system (PTS)

Shown on model 210 up to 30.6.99

Scheme 25

Warning indicator, location - GF54.65-P-4104-02AD

MODEL 210 as of 01.07.99 with CODE (220a) Parktronic system (PTS)

Model 210 as of 1.7.99

Scheme 26

Warning display, location / task / design / function - GF54.65-P-4104A

MODELS 140,163,168, 202, 208, 210, 215, 220 with CODE (220a) Parktronic System (PTS)

Illustrated on model 140

Scheme 27