2000 BMW 540i alarm

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Central Body Electronics ZKE III
Central Body Electronics (ZKE III)
Purpose of the System
The Central Body Electronics (ZKE III) system manages the following functions:
GM III
• Windshield Wiping/Washing
• Windsheild Rain Sensor (AIC)
• Headlight Washing
• Tailgate Wiping/Washing
• Interior Lighting
• Central Locking
• Keyless Entry
• Key Memory
• Power Trunk Release
• Electric Opening of Tailgate
• DWA Alarm System
• Servotronics
• Consumer Cut-off/sleep mode
• DiagnosisDriver’s Door Switch Block/
Module
• Power Windows
• Mirror Adjustment/Memory/
HeatingPassenger’s Door Module
• Mirror Adjustment/Memory/
Heating
• Power Windows
Sunroof Module
• Power SunroofSeat/Mirror/ Steering Column
Memory Module
• Seat Adjustment/Memory
• SteeringColumn Adjustment/
Memory
The ZKE III system was introduced on the E38 and is used in the E39 and E53. Most of the
functions operate the same on these vehicles with minor changes and added features to
the system.
ZKE III represents the combination of Body Electronics functions into one central control
module, the General Module (GM).

Central Locking
Purpose of the System
The Central Locking System provides locking/
unlocking of the entire vehicle from one central
exterior point. From the driver’s door or the
remote (key-less) entry, a lock/unlock request will
lock/unlock all exterior doors, luggage compart-
ment and the fuel filler flap.
From inside, the vehicle can be locked/ unlocked using a cen-
tral locking button located in the center console. Individual
doors can be unlocked manually by pulling twice on the inte-
rior door handle.
From 2000 MY
- if the vehicle has been double locked, press
the central locking button and pull the interior door handle
twice (alarm will sound when the door opens).
Locking the vehicle from the central switch will “single lock” all
doors, luggage compartment and not lock the fuel filler flap.
The Central Locking System utilizes the GM III and Door Modules to carry out all of the lock-
ing/unlocking features:
• Remote (key-less) entry is standard.
• When locked from the outside, the vehicle will double lock and arm the DWA System. The
ignition must be switched off and the driver’s door must be opened and closed.
• Selective unlocking from the outside of the vehicle. Unlocking from the driver’s door or
remote transmitter will only unlock the driver’s door and disarm the DWA System. A sec-
ond request will unlock the remaining doors and luggage compartment. This feature can
be modified for individual users in Key Memory to open all doors from a single request.
• A single central locking button is installed in the center console that will operate when all
of the doors are closed. Locking the vehicle from the central switch will “single lock” all
doors, luggage compartment and not lock the fuel filler flap. When unlocking, a single
request will unlock the driver’s door only. This feature can be modified for individual users
in Key Memory to open all doors and luggage compartment from a single request.
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Remote (Keyless) Entry FZV
Purpose of the System
The Remote Entry System offers the following:
• Locking/unlocking of doors, luggage compartment (tailgate), fuel filler lid.
• Selective unlocking of driver’s door (same as with key in the lock cylinder).
• Arming/disarming of DWA alarm system.
• Remote unlocking of the trunk (tailgate) only.
• Comfort opening of windows and sunroof.
• Interior lighting activation (search mode).
• Panic mode alarm activation.
• Changing code signals - coded signals from transmitter change with every operation.
• Automatic correction for up to 1000 erroneous activation signals.
• Transmitter initialization procedure - including up to four key operation and Key Memory.
• Replacement batteries.
• Low transmitter battery in vehicles equipped with Check Control.
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Anti-Theft (DWA) System
Purpose of the System
The DWA alarm system offers vehicle protection by monitoring the doors, hood, interior,
luggage compartment and vehicle tilting. When activated, DWA deters theft by sounding
an alarm siren for 30 seconds, flashing the low beam headlights (high beam on Xenon
equipped models) and four way flashers for 5 minutes.
The control electronics for DWA are integrated in the general module. The DWA - LED
indicator is located in the rear view mirror (E38 in the top center IHKA grille).
The system is “armed/disarmed” from the driver’s door lock cylinder, remote transmitter or
luggage compartment lock cylinder. The alarm is immediately deactivated when disarmed
with the key in the driver’s door lock cylinder (may be deactivated in Conversion) or remote
transmitter.
The GM utilizes existing components and/or circuits as part of the DWA system:
• Door latch switch/sensor contacts (door open/closed).
• Trunk lid switch contact (monitored for closed trunk).
• Trunk lock key position switch (located on the trunk lock, this switch signal prevents
DWA from activating if armed when the trunk is opened with the key).
• Hood switch (monitored for closed hood, located under the hood).
• DWA status LED (part of rear view mirror).
The additional components required are:
• Interior Sensor • DWA Siren • Tilt sensor
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System Components
Interior Sensor FIS (up to 99 MY): The interior sensor is mounted in the center of the
headliner panel. Due to the design of the vehicles interior, the sensor is uni-directional and
must be installed in the proper direction to ensure proper operation of the system.
When the alarm system is armed, the sensor emits electromagnetic waves at a frequency
of 2.45 GHz. As long as nothing is moving in the vehicle, the waves as bounced back to
the sensor at the same frequency. The sensor monitors these bounced back waves as an
indication that nothing is disturbed within the vehicle.
If a foreign object enters the vehicle, the frequency of the bounced back signal changes.
The sensor monitors the changed frequency and triggers the alarm.
Every time the DWA system is armed, the
sensor adapts to what ever objects might be
stationary in the interior.
This allows packages or objects to be left
inside the car without effecting the operation
of the system. The sensitivity of the sensor is
set so that the moving object must be at least
as large as a bumble bee. This prevents a
false alarm from occurring from small insects
that might be caught in the vehicle.
The FIS is switched OFF when the vehicle is locked two times within ten seconds. The LED
will flash one time for confirmation. This allows the sensor to be switched OFF to avoid false
alarms when the windows are left open for venting.
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Interior Sensor UIS (after 99 MY):Similar to the FIS, the UIS monitors the vehicle interi-
or for motion. The UIS uses ultrasonic sound wavs instead of microwaves (less suceptable
to magnetic interference). The UIS is a combined transmitter and receiver.
The interior sensor is mounted in the center of the headliner panel. Due to the design of the
vehicles interior, the sensor is uni-directional and must be installed in the proper direction
to ensure proper operation of the system (trim cover ensures directional installation).
Every time the DWA system is armed (signal STDWA), the sensor adapts to what ever
objects might be stationary in the interior. The sensor emits ultra sonic waves in a pro-
grammed timed cycle. It receives echos of the emitted waves.
The UIS amplifies the received sound wave signals and compares them with the transmit-
ted waves. The UIS also checks the incoming echos for background hiss (wind noise
through a partially open window) and adapts for this.
• If the echos are consistently similar, no movement is detected.
• If the echos are altered, (inconsistent), the UIS determines motion in the interior com-
partment.
If motion is detected, the UIS changes to a constant cycle and the echo is compared again.
If the inconsistency is still present the UIS sends the activate siren signal (INRS) to the GM.
The UIS is switched OFF when the vehicle is locked two times within ten seconds. The LED
will flash one time for confirmation. This allows the sensor to be switched OFF to avoid false
alarms when the windows are left open for venting.
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Tilt Sensor (Liquid Type - E38/E39 to 97 MY): The Tilt Sensor consists of a conductive
liquid chamber, a processor board and metal probes (located in the luggage compartment).
The probes are submersed in the liquid and produce a resistance value dependent on the
tilt of the sensor (angle of vehicle). This resistance value becomes the static point when the
DWA System is armed.
If the vehicle is jacked-up or lifted,
the angle of the liquid changes
producing a change in the resis-
tance value. The sensor recog-
nizes this change and signals the
GM to activate the DWA alarm.
The resets at the new angle. This
allows the DWA to remain armed
and re-activate the alarm if the
vehicle is moved again.
As with the interior sensor, the tilt sensor is also switched OFF when the vehicle is locked
two times within ten seconds. The LED will flash one time for confirmation. This allows the
sensor to be switched OFF for transportation purposes.
Tilt Sensor (Electronic Type from 98 MY): Located in the luggage comparment area,
the tilt sensor is an electronic sensing device with the sole purpose of monitoring the vehi-
cle's parked angle when DWA is armed.
The sensor requires three signal wires to func-
tion:
• KL 30 - Constant battery voltage
• Signal "STDWA"; switched ground input sig-
nal provided by the GM indicating DWA
armed/disarmed status.
The tilt sensor is used as a splice location for
the STDWA signal to the Siren and UIS int-
erior protection sensor.
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• Signal "NG"; switched ground output signal provided to the GM. The signal is used for
two purposes,
1. As a momentary acknowledgment that the tilt sensor received STDWA and is cur-
rently monitoring the vehicle angle.
2. If the tilt sensor detects a change in the vehicle's angle when DWA is armed, signal
NG is switched to inform the GM to activate the siren.
When the tilt sensor receives the STDWA signal from the GM it memorizes the vehicle's
parked angle. The angle of the vehicle is monitored by the solid state electronics. Once
armed, if the angle changes, the tilt sensor provides a switched ground signal to the GM
to activate DWA.
As with the interior sensor, the tilt sensor is also switched OFF when the vehicle is locked
two times within ten seconds. The LED will flash one time for confirmation. This allows the
sensor to be switched OFF for transportation purposes.
Glass Breakage Sensors (Early E38 - before FIS Sensor): The door windows (includ-
ing the rear quarter glass wire loop) are monitored by inductive sensors mounted on the
inside of the door behind the trim panel. A closed window is recognized by a magnetic plate
on the glass lining up with the sensor.
If the glass is broken, the plate falls away and the signal from the sensor changes and the
GM will activate the alarm.
Alarm Siren: The alarm siren is mounted in the rear wheel well, behind the inner wheel
housing cover (early E38 used an alarm horn). The E53 alarm siren is located in the left side
of the engine compartment.
The siren contains electronic circuitry for producing the warn-
ing tone when the alarm is triggered. The siren also contains a
rechargeable battery that is used to power the siren when the
alarm is triggered.
The rechargeable battery will allow the siren to sound if it or the
vehicle’s battery is disconnected. The siren battery is
recharged, from the vehicle’s battery, when the alarm is not in
the armed state.
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