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Central Body Electronics - Overview BMW Z4 E85/E86

Body Electrical 35 illustrations ~6544 words

General Module V (GM V)

New features of the GM V include

  1. A more powerful processor
  2. 2 outputs for switching off electrical equipment (VA1 and VA2)
  3. Pulse-width modulated output for the interior lighting

Central Locking System

  1. The glove compartment is not integrated in the central locking system
  2. The storage compartment is integrated in the central locking system
  3. The low lock is fitted on the driver's side
  4. The contact for the hotel setting (trunk lock barrel) is not fitted

Seat Adjustment/Memory Functions

  1. The memory functions are only available for the driver's seat

Soft-Top Module (CVM) 4

  1. The enable signal for relay 2 for activating the rear window heater is generated by the soft-top module 4.
  2. The soft-top position is only detected at the limits of movement in either direction.

Antitheft Alarm System

  1. Operation of the trunk emergency release sets off the alarm if the anti-theft alarm system is armed.

Temperature Switch

  1. The temperature switch is located at the front on the left under the cover on the vehicle underbody.

Scheme 49

Scheme 49

Purpose Of The System

The function of the power windows is based on the function of those fitted on the E46 convertible.

Scheme 50

Scheme 50: Purpose Of The System

Components

The system consists of the following components

  1. Door locks with Hall-effect sensors
  2. General module 5
  3. Power window switches
  4. Window regulator motors

Door Locks With Hall-Effect Sensors

The door locks each contain a Hall-effect sensor for detecting the door position. In addition, there are two Hall-effect sensors in the driver's door which monitor the position of the lock barrel.

The Hall-effect sensors signal to the general module 5 that one of the doors is being opened, for example. The general module 5 briefly lowers the window in the door concerned. The window has to be lowered in order that the door can be opened.

General Module 5

The General Module is attached to the lower trim behind the glove compartment. The general module controls the power window functions. It receives the input signals from the door locks and the switch units, and monitors the power consumption of the electric motors that drive the window regulator mechanisms.

The E85 has no anti-trap function available. Consequently, one-touch closing on the passenger side is not allowed. One-touch closing on the driver's side is possible at key positions starting from terminal 15.

One-touch opening is possible at key positions starting from terminal 15 on the driver's and passenger sides.

Scheme 51

Scheme 51: General Module 5

Scheme 52

Scheme 52

The power-window switches are integrated in the arm rests of the door trim panels. The driver's-side power-window switch unit also incorporates a switch for the passenger-side window, the buttons for the door mirrors and the mirror folding button.

Each power-window switch has four positions. Those positions trigger different functions depending on country-specific variations and the programming of the general module. The passenger-side power-window switch also has four positions.

Window Regulator

The window regulator mechanisms are cable operated. The drive motor is not monitored by Hall-effect sensors.

The central locking system function is based to a large extent on the function of the system on the E46.

New System Features

  1. The storage compartment is integrated in the central locking system function.
  2. The glove compartment is not operated by the central locking system.
  3. The trunk lock does not have a hotel setting switch that operates in conjunction with the lock barrel. It is locked by means of a cable mechanism.
  4. The driver's door lock is the low lock from the E65.
  5. The Easy Open/Close function cannot be activated with the remote control.

Scheme 53

Scheme 53

The system consists of the following components

  1. General module 5
  2. Driver's door lock
  3. Central locking servo unit, driver's side
  4. Central locking servo unit, passenger side
  5. Central locking servo unit, storage compartment
  6. Central locking servo unit, fuel filler
  7. Central locking servo unit, trunk
  8. Trunk lock switch for "deactivating" the anti-theft alarm system
  9. Trunk release button in passenger compartment
  10. Centerlock button
  11. Remote control receiver in rear-view mirror base

Scheme 54

Scheme 54: General Module

Scheme 55

Scheme 55

The General Module controls the central locking functions on the E85.

Driver's-Door Lock

The driver's door lock on the E85 is an Low lock. Compared with the lock used on the E46, this unit incorporates two Hall-effect sensors. The general module analysis the signals from those sensors and locks/thief-proofs or unlocks the vehicle accordingly.

The order of the signals determines how they are interpreted, i.e. as lock/thiefproof or unlock. By the use of two Hall-effect sensors and the intelligent analysis of their signals, errors when locking/thief proofing or unlocking the vehicle are prevented.

Detection of a rising edge starts a counter which is stopped again as soon as both signals (SNU 1 and SNU 2) are present. Within a valid time window, the request to lock/thiefproof or unlock is set. As long as the key is held in the turned position, the request to lock/thiefproof or unlock remains valid. If either of the two signals (SNU 1 or SNU 2) is lost, the request is reset again.

Central Locking Servo Units

The door lock is a single unit. That unit incorporates the servo motor, the door lock mechanism and the Hall-effect sensors.

Scheme 56

Scheme 56: Central Locking Servo Units

Scheme 57

Scheme 57

Storage Compartment

The storage compartment is integrated in the central locking system and can be locked/unlocked using the remote control, the driver's-door lock or the Centerlock button. Inside the trunk on the bulkhead there is an emergency release.

The storage compartment is between the passenger seat and the driver's seat in the bulkhead trim.

Scheme 58

Scheme 58: Storage Compartment

Scheme 59

Scheme 59

Fuel Filler Flap

The fuel filler flap is incorporated in the central locking system. There is an emergency release for the fuel filler flap inside the trunk on the right side under the trunk lining.

Trunk Lock

The trunk lock and lock barrel are identical with those on the E46. The difference between the E85 and the E46 is the linkage between the lock and the lock barrel. Instead of a rod linkage, a cable is used. The lock is released (manually) by a cable mechanism operated by the key. The switch for the anti-theft alarm system is incorporated in the lock barrel.

The trunk lock can be operated manually or electrically. The Basic module 5 controls the motor in the trunk lock by means of the "Trunk lock, motor unlock" signal. The locking pawl is moved to the release position by the drive pin. The locking pawl releases the latch which can then rotate into the disengaged position by the action of the tension spring. The trunk can then be opened. The locking pawl releases the microswitch button from the depressed position. The microswitch switches the trunk light on.

The trunk can be unlocked from the lock barrel. The trunk lock can be unlocked by means of a cable operated by the lock barrel.

The locking pawl is pulled to the release position by the cable. The locking pawl releases the latch which can then rotate into the disengaged position by the action of the tension spring. The trunk can then be opened.

Emergency Trunk Release

The emergency trunk release operates in a similar manner to the mechanical method using the key. The only difference is the actuating device.

A person locked inside the trunk can pull the release handle on the inside of the trunk. The handle is connected to a release cable. Pulling the release handle releases the trunk lock in a similar manner to the preceding description (mechanical method) so that the trunk can be opened.

The seat adjustment and memory functions are based to a large degree on those on the E46. The memory functions are only available for the driver's seat.

Scheme 60

Scheme 60: Purpose Of The System

Scheme 61

Scheme 61

Seat Heating

The seat heating functions are based on those on the E46. The seat heater is activated and controlled by means of the seat heater button integrated in the center console.

Scheme 62

Scheme 62: Seat Heating

Scheme 63

Scheme 63

The function of the wash-wipe system is based on that of the E46 wash-wipe system.

The wiper system consists of the following components

  1. windshield washer system
  2. Steering-column switch
  3. Rain/light sensor
  4. Headlight washer system

Scheme 64

Scheme 64

A rain/light sensor is available as an option. The headlights are switched on/off automatically by the rain/light sensor according to the ambient light conditions. The rain/light sensor detects the presence of water on the windshield and switches the windshield wiper on and off accordingly.

The rain/light sensor is fitted in the base of the rear-view mirror and it consists of optical sensors. The RLS has 2 optical sensors integrated in the casing of the automatic interval control module. The 2 new sensors supplement the otherwise unchanged wiper interval control function of the automatic interval control module as follows

  1. An ambient-light sensor detects the light intensity above the vehicle within a wide scanning angle.
  2. A forward light sensor detects the light intensity within a narrow scanning angle directly ahead of the vehicle.

An internal processor calculates from the readings taken by the ambient and forward light sensors whether the preconditions for switching on the lights are present.

The RLS checks the following preconditions for switching on the headlights

  1. Twilight
  2. Complete darkness
  3. Entry in underground car park
  4. Entry in tunnel

If any of the above conditions is met, the rain/light sensor on the E85 sends the information via the K-bus to the light switch center. In order to be able to control the headlights automatically, the rain/light sensor must be activated by a separate light switch setting on the light switch center.

If the light switch on the light switch center has been set to the position for automatic control of the headlights, the exterior/instrument panel lights are switched on by the light switch center. The preconditions for switching on the lights are as follows

  1. One of the rain/light sensor conditions listed above is met.
  2. The fog lamps are switched on.

Note. If the above conditions exist, the lights can only be switched off by switching off the fog lamps. In addition, the lights are switched on if any of the following faults occur: The rain/light sensor detects a sensor fault. There is a fault in communication between the rain/light sensor and the light switch center.

The following lights are controlled by the light switch center

  1. If terminal R is "ON," the side lights, the number-plate light and the instrument panel lights are switched on.
  2. If terminal 15 is "ON," the dipped-beam headlights are also switched on. If only the side lights are required at that setting, the switch on the light switch center must be manually set to Side lights "ON."
  3. When the ignition switch is at position "0," the exterior/instrument panel lights are switched off.

The switching thresholds of the rain/light sensor can be set to 2 different levels using the Car Memory function.

Safety note

Automatic control of the headlights is not a substitute for individual assessment of the light/visibility conditions (e.g. fog) by the driver. In order to avoid safety risks in such situations, the lights must be switched on manually by the driver.

The rain sensor controls the windshield wiper interval in rain or snow.

Note. If the wiper switch is set to intermittent wipe, the activation condition is detected above a certain wiper frequency. When the vehicle leaves the factory, that wiper frequency is set to 15 wiper cycles per minute. The sensitivity of the rain sensor can be set to four different levels using the knurled adjuster on the wiper switch.

The E85 will be available with a manual or an electro-hydraulic soft-top. On vehicles with the electro-hydraulic soft-top, the Soft-top module IV will be fitted. There will also be a hardtop for the E85.

The system has the following predecessor systems

Predecessor SystemsSeriesModelDates
Soft-top Module 1E36Convertible1995-3/2000
Soft-top Module 2E46CConvertible03/2000 to present
Soft-top Module 3E52Z803/2000 to present

SERIES PREDECESSOR SYSTEMS

Fully Automatic Soft-Top Components

The system consists of the following components

Scheme 65

Scheme 65: Fully Automatic Soft-Top Components
  1. Fully automatic soft-top
  2. Soft-top module 4 (CVM4)
  3. Hall-effect sensors (2) for Soft-top position
  4. Hall-effect sensors (2) for Windshield Rail lock position
  5. Locking servo unit, front
  6. Hydraulic pump
  7. Hydraulic pump relays (2)
  8. Left (hardtop detection) and right hardtop locating socket contacts
  9. Microswitch for variable-size soft-top stowage compartment
  10. General module 5
  11. Instrument cluster
  12. Heater control panel
  13. Relay 1 for rear window heater
  14. Relay 2 for rear window heater
  15. Rear window heater
  16. Soft-top control button with LED (for soft-top DOWN)
  17. Soft-top control button with LED (for soft-top UP)

CVM4

The Soft-top module controls and monitors the hydraulic and electrical positioning and locking systems of the soft-top. In addition, it registers the position of the soft-top and records any faults that occur.

The Soft-top module IV is located behind the driver's seat and underneath the top part of the side trim panel.

Scheme 66

Scheme 66: Soft-Top Position Sensors

The Hall-effect sensors detect the soft-top position when it is fully raised or fully lowered into the stowage compartment. The two sensors are fitted to the left-hand main pillar.

Hall-effect sensor 1 signals to the Soft-top module 4 that the fully automatic soft-top is in the fully raised position. Hall-effect sensor 2 signals to the Soft-top module 4 that the fully automatic soft-top is in the fully lowered position in the stowage compartment.

Scheme 67

Scheme 67

Windshield Top-Rail Lock

The Hall-effect sensors (2) on the windshield top-rail locking mechanism signal the position of the locking latches. They are located on the left-hand locking mechanism on the front roof bow of the fully automatic soft-top.

Lock Servo Unit

The lock servo unit locks and unlocks the windshield top-rail lock. The lock servo unit is positioned centrally on the front roof bow of the fully automatic soft-top.

Scheme 68

Scheme 68: Lock Servo Unit

Scheme 69

Scheme 69

Hydraulic Pump

The hydraulic pump generates the necessary pressure for the hydraulic piston to move the soft-top. The hydraulic pump is part of the hydraulic servo unit on the left main bearing of the fully automatic soft-top.

Scheme 70

Scheme 70: Hydraulic Pump

Soft-Top Relays

The relays control the hydraulic pump for raising/lowering the soft-top. The relays are fitted behind the passenger airbag. The relays (color: pink) for the hydraulic pump are plugged into a relay panel on the K-bus junction box. The junction box is located behind the glove compartment and the passenger airbag.

Stowage Compartment Switch

The microswitch signals to the Soft-top module 4 that the stowage compartment base is at its lowest position. That signal is one of the preconditions for lowering the soft-top. The microswitch is located inside the trunk. The microswitch is fitted inside the trunk on the positioning mechanism (in the center of the trunk bulkhead) for the stowage compartment base.

General Module V

The GM V controls the function of the window regulators when the fully automatic soft-top is being raised or lowered.

Instrument Cluster

The instrument cluster calculates the vehicle road speed and the outside temperature from the information supplied by the sensors (wheel-speed and outside-temperature sensors). The vehicle road speed and the outside temperature are placed on the K-bus where they can be read by the Soft-top module 4.

The vehicle road speed and the outside temperature are among the preconditions for enabling raising/lowering of the soft-top.

Heater Control Panel

The heater control panel receives the enable signal for the rear window heater and switches the rear window heater on.

The button for the rear window heater is integrated in the heater control panel. The heater control panel receives the enable signal for relay 2 for the rear window heater.

Rear Window Heater

The rear window heater is supplied with power via relay 1 and relay 2 and is switched on by the rear window heater button. Relays 1 and 2 for the rear window heater pick up, thereby connecting the rear window heater to terminal 3. Relay 2 must have been enabled.

Soft-Top Control Buttons

The soft-top control buttons are fitted in the center console.

The soft-top control buttons are make-switches that connect to ground. The Soft-top module 4 controls the soft-top UP or DOWN movement.

Principle Of Operation

The Soft-top module IV controls the raising and lowering of the electro-hydraulic soft-top in response to the commands from the soft-top control buttons.

Preconditions for raising/lowering that are detected directly by the Soft-top module IV

  1. Hall-effect sensor 1 for the windshield top-rail lock signals that the windshield top-rail lock is disengaged (soft-top unlocked)
  2. Hall-effect sensor 2 for the windshield top-rail lock signals that the windshield top-rail lock is engaged (soft-top locked)
  3. The Hall-effect sensor (for soft-top raised) on the hinge of the main pillar signals that the soft-top is raised, or
  4. The Hall-effect sensor (for soft-top lowered) on the hinge of the main pillar signals that the soft-top is stowed in the stowage compartment
  5. The hardtop detector signals that no hardtop is fitted
  6. The microswitch of the variable-size stowage compartment indicates that the stowage compartment base it at its lowest position
  7. The Soft-top module IV has not detected any faults on the system as a whole during its internal system test Other conditions that are detected indirectly by the Soft-top module IV
  8. Ignition key at position R at least
  9. Window not closed
  10. Vehicle stationary (road speed < 4 km/h)
  11. No short circuit and no circuit break present
  12. Outside temperature is not below the limit of approx. -20 °C
  13. Soft-top button pressed

The Soft-top module IV exchanges information via the K-bus. The Soft-top module IV monitors the Hall-effect sensors for plausibility of the signals and correct function. There are 2 Hall-effect sensors fitted to the hinge of the main pillar. There are 2 Hall-effect sensors on the front roof bow of the electrohydraulic soft-top.

Response To High/Low Voltage

The voltage range of the Soft-top module IV is 9 V to 16 V.

Method Of Operation Of Soft-Top Stowage Compartment Lock

The soft-top stowage compartment lock holds the soft-top in place when it is fully stowed in the compartment. When the softtop is raised, it locks onto the windshield top rail.

Operation Of Soft-Top Stowage Compartment Lock When Lowering Soft-Top

When the electro-hydraulic soft-top is fully lowered into the stowage compartment it is automatically locked in position. This is effected by the electro-hydraulic soft-top being lowered to a position in the stowage compartment where the mechanical locking mechanism engages.

The Hall-effect sensor on the hinge of the right-hand main pillar signals to the Soft-top module IV that the electrohydraulic soft-top is in the fully lowered (stowed) position. The locking latches on the electro-hydraulic soft-top are then also engaged. The locking latches are controlled by the Soft-top module IV.

When the electro-hydraulic soft-top is in the fully lowered (stowed) position, the Soft-top module IV switches the hydraulic pump off. The relay is switched off by virtue of the fact that it is no longer enabled by the Soft-top module IV. The electro-hydraulic soft-top is now fully lowered into the stowage compartment.

Operation Of Soft-Top Stowage Compartment Lock When Raising Soft-Top

When the electro-hydraulic soft-top is raised, the stowage compartment catch is released, the locking latches disengaged and the soft-top raised out of the stowage compartment. On the windshield top-rail, the locking latches engage and lock the electro-hydraulic soft-top in position.

Operation Of Soft-Top Stowage Compartment Lock

The soft-top stowage compartment lock mechanism engages the latches of the fully automatic soft-top when it is fully lowered into the stowage compartment. When the fully automatic soft-top is raised, the latches are engaged in the windshield top rail.

The fully automatic soft-top is now fully lowered into the stowage

Operation Of Soft-Top Control Buttons

The soft-top control buttons for controlling the soft-top UP and DOWN actions are switches that connect to ground. Closing the connection to ground signals to the Soft-top module 4 that raising or lowering of the fully automatic soft-top has been requested.

Operation Of Hall-Effect Sensors

The Hall-effect sensors signal the position (LOCKED or UNLOCKED) of the locking latches to the Soft-top module 4.

Operation Of Soft-Top Relays

The Soft-top module 4 controls the relays. The 2 relays for the hydraulic pump are controlled as required (for raising or lowering soft-top) by the Soft-top module The relays are wired in such a way that the hydraulic pump action is reversible. The relays are controlled by the Soft-top module 4 via Highside switches. On a High-side switch, the transistor connects positive through.

Soft-Top Latch For Locking To Windshield Top Rail

The locking latches are closed when they locate in the windshield top rail. The left and right locking latches are closed when they locate in the windshield top rail. The rotation of the DC motor is transmitted to spindles. The spindles drive linkages. The action of the linkages is transmitted to the locking latches. The locking latches lock/unlock the fully automatic soft-top to/from the windshield top rail.

The position of the locking latches is detected by Hall-effect sensors 1 and 2

Microswitch For Variable-Size Soft-Top Stowage Compartment

The microswitch signals to the Soft-top module 4 that the stowage compartment base is at its lowest position. The Soft-top module 4 is informed by the microswitch that the movable stowage compartment base is at its lowest position. The microswitch is a make-switch that connects to earth.

GM5

The general module 5 opens or closes the windows on instruction from the Soft-top module The general module 5 stores the current status of trunk and window position. The general module 5 places the following information on the K-bus when it starts up

  1. Current status of trunk and windows
  2. Changes to current status of trunk and windows

Examples of current status information are

  1. Window closed; window open
  2. Trunk closed; trunk open.

(The signal for the trunk status is present but is not required by the Soft-top module 4)

The general module 5 receives the control commands for raising and lowering the windows from the Soft-top module The Soft-top module 4 sends the control commands via the body electronics bus before and after raising/lowering the soft-top. The precondition for lowering the windows is that at least one window is closed.

If the windows are already open before the soft-top is raised/lowered, and if one of the two soft-top control buttons remains pressed (2 s) after the soft-top has been fully raised/lowered, the windows are closed. Closing of the windows is stopped as soon as either of the softtop control buttons is released or the window mechanism detects that the window is closed (at limit of movement).

Soft-Top Stowage Compartment Lock

The locking latches are closed when the soft-top is stowed in the stowage compartment and the soft-top locked in position. As soon as the fully automatic soft-top is stowed in the stowage compartment, the locking latches close.

Soft-Top Module Iv Time-Out Function

If the soft-top control button remains pressed after the soft-top has stopped moving, the Soft-top module IV detects a fault. The fault is interpreted as "Short to ground on soft-top button or one of the leads" and the fault is recorded in the Soft-top module fault memory. However, the electro-hydraulic soft-top can still be moved to a safe parked position using the other soft-top control button/ lead, which is still functioning. If the button is released while the soft-top is still in motion, the soft-top is stopped (safety function).

Once the fault has been rectified and terminal R switch off and on again, the electro-hydraulic soft-top can be controlled by the soft-top button again.

Diagnosis

The diagnostic functions of the Soft-top module IV are to a large degree identical with those on the E46. However, fewer signals are analyzed on the E85 than on the E46 because there are fewer components on the E85.

Soft-Top Module 4 Internal Check

The internal functions of the Soft-top module 4 are checked under the following circumstances

  1. When the power is switched on
  2. When terminal R is ON
  3. Before the soft-top is raised/lowered

If a system fault is detected, movement of the soft-top is stopped immediately. The fault detected is recorded in the fault memory of the Soft-top module If the nature of the fault allows, the soft-top can be moved to the nearest safe parked position using one of the soft-top control buttons.

Control Button For Raising Soft-Top

A short circuit on the control button for raising the soft-top would raise the soft-top. The soft-top can still be moved to a safe parked position using the functioning control button for lowering the soft-top.

Control Button For Lowering Soft-Top

A short circuit on the control button for lowering the soft-top would lower the soft-top. To prevent the soft-top lowering, the functioning control button for raising the soft-top can be used to move the soft-top to a safe parked position.

Electric Locking System

The electric locking system is fitted with an overload protection circuit. The overload protection circuit has a time-out function as well as the hardware systems. In the event of misuse, e.g. while the soft-top is in motion, the time-out function disables the fully automatic soft-top function. After a certain time (when time-out has elapsed) the fully automatic soft-top function is restored.

Faults On Peripheral Systems

During the internal check and while the soft-top is being raised/lowered, the signals from peripheral systems are checked for plausibility. Those signals must be within the defined valid operating ranges.

Examples of peripheral system signals are

  1. Outside temperature
  2. Vehicle stationary signal
  3. Signals from the fully automatic soft-top, etc.

Storage Of Faults

Faults are stored in the order in which they occur. The Soft-top module 4 has up to 16 "fault storage locations" available in its fault memory.

Status Signals From Soft-Top Module 4

The Soft-top module 4 supplies the general module 5 and all other bus nodes with the current status signals. The Soft-top module 4 provides the following status signals

  1. Reset
  2. Status request
  3. Ready after reset

General Module 5 Window Regulator Safety Function

The general module 5 stops the windows being closed immediately with the loss of the Close windows signal.

Scheme 71

Scheme 71: Manual Soft-Top

The system consists of the following components

  1. Manual soft-top
  2. General module 5
  3. Heater control
  4. Left and right hardtop locating socket contacts
  5. Relay 1 for rear window heater
  6. Relay 2 for rear window heater
  7. Rear window heater
  8. Hall-effect sensor for detecting when soft-top is raised and locked to the windshield top rail (enable signal for relay 2)
  9. Button lock for manual soft-top

The rear window heater cannot be switched on until the relay is enabled according to the enabling conditions.

As with the hardtop, the rear window heater is switched on by the rear window heater button. Relays 1 and 2 for the rear window heater pick up, thereby connecting the rear window heater to terminal 3. Relay 2 must have been enabled.

Relay 2 is enabled by the Basic module 5 which sends a message via the K-bus to the heater control panel. The general module 5 does not send that message unless the following preconditions are satisfied

  1. The Hall-effect sensor on the manual soft-top signals that the soft-top is raised and locked to the windshield top rail.

Hardtop Detection

Hardtop detection prevents the soft-top being raised when the hardtop is fitted. When a hardtop is fitted, the right-hand hardtop locating socket contact is used to detect the presence of the hardtop. The hardtop's rear window heater is supplied with power via the left-hand hardtop locating socket contacts (right and left).

Button Lock for Manual Soft-Top

The button lock is integrated in the central locking system.

When stowed in the stowage compartment, the soft-top is locked in place by a catch. That catch has to be released in order to raise the manual soft-top. The button at the top of the bulkhead trim is for releasing the catch.

Hardtop Components

The system consists of the following components

  1. Hardtop
  2. Heater control
  3. Left and right hardtop locating socket contacts
  4. Relay 1 for rear window heater
  5. Rear window heater

The rear window heater is switched on by the rear window heater button. The button is fitted in the heater control panel (center console). The button is a make-switch that connects to earth; the LED lights up when the switch is on.

Relay 1 for the rear window heater picks up, thereby connecting the right-hand hardtop locating socket contacts to terminal 3. When the hardtop is fitted, the left-hand hardtop locating socket contact is the input (terminal 30) of the rear window heater. The righthand hardtop locating socket contact is connected to earth.

Note. (Rear Window Heater Button): When the button is pressed in, the LED is always on, regardless of whether the rear window heater can actually be operated or not.

The familiar version 3.3 electronic immobilizer is fitted on the E85.

Scheme 72

Scheme 72: Purpose of the System

The anti-theft alarm system on the E85 is based on the system used on the E46.

Disabling Tilt Sensor

The tilt sensor are temporarily disabled under certain circumstances.

Trunk Emergency Release

If the trunk emergency release is operated from inside, the alarm is set off if the anti-theft alarm system is armed.

Scheme 73

Scheme 73: Trunk Emergency Release

The tilt sensor are temporarily disabled under the following circumstances

  1. For the first 30 seconds after the anti-theft alarm system is armed
  2. Once the anti/theft alarm system has been armed, while either of the doors or the trunk is open (30-second inhibition period does not start until they are all closed)

The trunk can be released from inside the trunk in an emergency. Operation of the trunk emergency release sets off the alarm if the anti-theft alarm system is armed.

Introduction

The Park Distance Control system is familiar. On the E85, it is a 4-channel system.

Scheme 74

Scheme 74: Introduction

This chapter describes the alterations to the central body electrical system (ZKE), "electrical consumer unit shutdown" (VA) and "sleep mode" as compared to the E46 electrical system.

Consumer Unit Shut-Down

There are 2 outputs for consumer unit shut-down.

Sleep Mode

New conditions

K-Bus Messages

New messages

Consumer Shut-Down

The outputs VA1 and VA2 are available for consumer unit shut-down. The general module 5 has been expanded. There is now a second output available for consumer unit shut-down (VA). The consumer unit shut-down function switches consumer units to Sleep mode after 16 min.

Consumer Unit Shut-Down 1 (VA1)

Consumer unit shut-down output 1 is factory-configured as a pulse-width modulated output. The consumer units connected to consumer unit shut-down output 1 are the following

  1. Storage compartment light
  2. Trunk light
  3. Reading lights

In the event of an overload or short circuit, consumer unit shut-down output 1 is switched off by the general module 5 unless there is no load connected to the output (open load). Once switched off, the output is switched on again by terminal R "OFF/ ON" provided the fault (overload or short circuit) is no longer present.

Consumer Unit Shut-Down 2 (VA2)

Consumer unit shut-down output 2 is available as a permanent general module 5 output.

Consumer unit shut-down output 2 is overload and short-circuit proof. The consumer units connected to consumer unit shut-down output 2 are the following

  1. Illuminated shifting gate on center console (USA version)
  2. Sequential Manual Transmission control unit

The permanent consumer unit shut-down output 2 is intended for electronic control units. The electrical control units require a permanent output as otherwise they would not be able to function.

The preconditions for Sleep mode are the following

  1. Window regulators deactivated for 1 s
  2. Consumer unit shut-down and interior lighting passive
  3. Diagnostic mode not active
  4. K-bus in Sleep mode
  5. On "Go to Sleep Mode" signal after 1 s or within 30 s of the anti-theft alarm system being armed

The K-Bus now contains messages that may be addressed to all or multiple control units.

The diagnostic capabilities of the general module 5 have been extended. The general module 5 can distinguish between the following load conditions at the consumer unit shut-down outputs

  1. Overload
  2. Short circuit
  3. No load connected (open load)

The various faults can be diagnosed.

Consumer unit shut-down output 2 (VA2) is overload and short-circuit proof. An overload is detected by the general module 5.

Options offered on the E85 are electrochromatic mirrors, the mirror folding function and the winter package.

The temperature switch for the heated washer jets is at the front on the left under the cover on the vehicle underbody.

Scheme 75

Scheme 75: New System Features

The system consists of the following components

  1. Door mirrors on driver's side and passenger side
  2. Mirror adjuster button, driver's side
  3. Rear-view mirror (if electrochromatic option fitted)
  4. Mirror folding module (Located at the base of the A pillar)
  5. Mirror heater
  6. Temperature switch
  7. Heated washer jets
  8. Temperature switch (switches on the heaters for the heated washer jets)

Headlights

The E85 headlights are fitted with halogen bulbs as standard for both the low and high beams.

Bi-xenon bulbs are available as an option. If the bi-xenon option is fitted, a dynamic beam-height adjustment system is also fitted. Lighting configurations for the E 85 are as follows

  1. US version with halogen headlights without manual beam height adjustment
  2. US version with dynamic beam-height adjustment and bi-xenon headlights

The US versions also have two sidemarker LEDs. They are integrated in the left and right side sections of the rear bumper.

Scheme 76

Scheme 76: System Overview

Scheme 77

Scheme 77

Scheme 78

Scheme 78: Front Light Cluster

Scheme 79

Scheme 79: Rear Light Cluster

Rear/Brake Light

The rear-light and brake-light bulbs are in separate compartments in the left and right light clusters. When the headlights are switched on, all bulbs in compartments 1 and 3 are switched on. Those bulbs have a power rating of 21 Watts. For the rear light function, all four bulbs are controlled by pulse-width modulation. This dims all four bulbs to 5 Watts.

During braking, the light switch center receives a signal from the brake light switch. The light switch center then applies 21 Watts to the bulbs in compartment In that way, the brake light function is performed.

Brake Force Display

In order to improve the reaction of other drivers to an emergency stop, the E85 has a Brake Force Display system. Its purpose is to reduce the likelihood of being driven into by the vehicle behind. The Brake Force Display function will only be available on the US version at series launch.

If a deceleration of more than 5m/s2 or an ABS signal is detected, the bulbs in compartment 3 are activated by the light switch centre. They too then receive the full 21 Watts of power. In this way, the brake light plus Brake Force Display function is performed.

Scheme 80

Scheme 80: Brake Force Display

Sidemarker Lights

The US version has two sidemarker lights in the rear plastic bumper panel. They are LED light units.

Bi-Xenon Headlights

The optional bi-xenon headlights represent a major advance in road illumination and headlamp range. Their function is identical to the bi-xenon headlights on the E46.

When the headlights are switched on using the steering column stalk, an electromagnet controls a movable beam-pattern screen in the ellipsoid module of the dipped-beam headlight. That screen then uncovers the high part of the headlight beam.

Note. If the headlight flasher function is required, the bi-xenon beam-pattern screen is not activated. Only the high-beam headlight (H7) is activated. The bi-xenon light reacts too slowly to that signal.

Light switch center

The light switch centre controls the entire exterior lighting system. The following components are integrated in the light switch centre, depending on equipment level.

  1. Light switch
  2. Switch for fog lamps
  3. Dimmer control for dashboard, instrument cluster and locator lighting (terminal 58)
  4. Photocell for detecting ambient light conditions

The light switch centre has the capability of adjusting the effective voltage at all outputs by means of pulse-width modulation. With the exception of those for the bi-xenon headlights and their beam-pattern screens, all output voltages are pulse-width modulated.

Control of the effective voltage levels by pulse-width modulation allows brightness fluctuations due to variations in the load on the vehicle's electrical system to be evened out. The electrical system voltage has to be higher than the desired effective voltage.

Scheme 81

Scheme 81

Rain/light sensor (RLS)

The E85 is available with a rain/light sensor (RLS) as an option. The headlights are switched on/off automatically by the rain/light sensor according to the ambient light conditions.

There are two additional optical sensors for the RLS integrated in the casing of the automatic interval control (AIC) module. The two new sensors supplement the otherwise unchanged wiper interval control function as follows

  1. An ambient-light sensor detects the light intensity above the vehicle within a wide scanning angle.
  2. A forward light sensor detects the light intensity within a narrow scanning angle directly ahead of the vehicle.

An internal processor calculates from the readings taken by the sensors whether the preconditions for switching on the lights are present.

The following conditions are checked for

  1. Twilight
  2. Complete darkness
  3. Entry in underground car park
  4. Entry in tunnel
  5. Precipitation such as rain or snow

Note. If the wiper switch is set to intermittent wipe, the precondition for switching on the lights is detected once the wiper frequency exceeds a pre-defined level (factory setting is 15 wiper cycles per minute). If the wiper switch is set to Speed I or II, the precondition for switching on the lights is constantly satisfied. If any of the above conditions is met, the RLS on the E85 sends the information to the light switch centre.

In order to be able to control the headlights automatically, the RLS must be activated by a separate light switch setting on the light switch centre.

In addition, the lights are switched on if any of the following faults occur

  1. The RLS detects a sensor fault.
  2. There is a fault in communication between the RLS and the light switch centre.

The following lights are controlled by the light switch centre

  1. If terminal R is "ON," the side lights, the number-plate light and the instrument panel lights are switched on.
  2. If terminal 15 is "ON," the side lights, the dipped headlights, the number-plate light and the instrument panel lights are switched on. If only the side lights are required at that setting, the switch on the light switch centre must be manually set to Side lights "ON."
  3. When the ignition switch is at position "0," the exterior/instrument panel lights are switched off.

The sensitivity of the RLS can be set by means of the Car Memory function.

Note. Safety note: Automatic control of the headlights is not a substitute for individual assessment of the light/visibility conditions (e.g. fog) by the driver. In order to avoid safety risks in such situations, the lights must be switched on manually by the driver.

Scheme 82

Scheme 82: Interior lights

Changes Compared To E46

The interior lighting is controlled by the general module V. In order to even out the light power fluctuations that are made more likely by the use of the NG engines (probability of high power draw by Valvetronic electric motors), the voltage for the vehicle lights is provided by means of a pulse-width modulated signal with a fixed frequency of 100 Hz. By varying the pulse width, and thereby the voltage, applied to the light bulbs, the fluctuations referred to above can be compensated for.

The general module V has a fault feedback function. If the power driver in the general module V detects the failure of a bulb, the output on the general module V is shut down. That means that no power is available at that output any longer. If the defective bulb is replaced and terminal R switched OFF/ON, power is available at the general module output again. The interior door handle lights and centre console lights as well as the ambience lights in the interior light unit are controlled by the light switch center.

The storage compartment also has a light. That light has a microswitch and two bulbs.

Scheme 83

Scheme 83: Changes Compared To E46