1999 BMW 750IL ESP

6
Central Body Electronics ZKE III
The following is an overview of new or changed features found on the E53 ZKE III variant:
• Passenger’s door module is incorporated into the passenger’s door switchblock.
• Sunroof module (SHD) is located on the P -Bus.
• The Central Locking system uses a door lock actuators with hall effect sensors.
• The GM III is responsible for the Key Memory feature.
The E53 ZKE III system continues to be a modular system consisting of the following:
•General Module III = Main controller for ZKE functions
•PM - SB/FT = Driver’s door switch block and door module
•PM - SB/BT =Passenger’s door module/Window switch
•PM - SHD =Sunroof module
•PM - SM =Seat/Mirror/ Steering Column memory module
•AIC = Rain Sensor (if equipped)
All of these modules communicate over the “K-Bus and P-Bus” for signaling purposes and
diagnosis.

Vehicle Memory: The owner is provided with a list of available system functions that can
be customized to their liking. Prior to delivery, the DISplus or MoDiC is used to encode the
owner’s chosen selections into the appropriate control modules.
These choices become a permanent function of the control module and can only be
changed by re-encoding with the DISplus or MoDiC at a BMW Center.
This feature has been available for some time via the ZCS Conversion Feature but has
never been fully utilized or officially presented to the vehicle owner as a feature of their vehi-
cle.
Key Memory: This feature provides the added convenience of identifying users of the vehi-
cle whenever a lock or unlocked signal is generated via the individual FZV keys. A maxi-
mum of four FZV keys can be used with the Key Memory feature.
Each of the four keys generate a unique key identification signal (key number) that is trans-
mitted simultaneously with the lock/unlock signals to the General Module. Key Memory
does not respond to Lock/Unlock requests from the drivers door lock.
Mostof the key memory functions require the vehicle be configured using the “KEY MEM-
ORY” function of the DIS or MoDiC. However, there are a few features that store settings
automatically without configuration such as IHKA blower speed and temp setting. The key
ID signal alerts the GM to communicate with select control systems over the K Bus to store
(when locked) or reset (when unlocked) certain driver adjustable settings.
There are features that function as both a Car & Key Memory feature.
Example; the Automatic Seat Adjustment feature is encoded as a Car Memory Function
with the following possibilities:
• When unlocking,
• When opening a door after unlocking
• Or not active at all.
If active, the seat positions are stored and reactivated by the Key Memory function for indi-
vidual users of the car.
Notes: _______________________________________________________________________
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Central Body Electronics ZKE III

Workshop Hints
Remote Key Initialization: The initialization of the FZV keys is required to establish the
Lock/Unlock signal synchronization with the GM. The initialization procedure provides the
GM with a key identification number and a “rolling code” for each key. If the initialization is
not performed, the GM will not respond to the key signals.
Up to 4 remote keys can be initialized. They must be initialized at the same time. Key ini-
tialization is only possible with the vehicle unlocked.
Procedure:
1. Close all doors and have all keys available.
2. Using key number 1, turn the ignition switch to KL
R, then switch off within 5 seconds and remove the
first key.
3. Within 30 seconds of turning the ignition switch to
“off” Press and holdbutton #2.
4. While holding button #2, press and release(“tap”)
button #1 three timeswithin 10 seconds.
5. Release both buttons. The LED in the key will flash
momentarily (except 2000 MY). The GM will imme-
diately lock and unlock the doors signaling a suc-
cessful initialization.
6. If additional keys need to be initialized repeat steps
3 - 5 within 30 seconds.
7. Switching the ignition to KL R completes the initiali-
zation.
NOTE: The key memory function of the GM responds
to the key identification number of each key. If the keys
are not initialized in the same order prior to initialization,
the key memory functions activated by the keys will not
be assigned correctly. Always initialize the keys in
the same order.
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Central Body Electronics ZKE III
1
2
615200101.eps

LED Status (Keys equipped with LED):
The following functions can be checked with the LED:
• Flashing LED when pressing a button.
Indicates that the data is being transmitted.
(battery voltage between 3.2 - 2.6 volts)
• No LED activity when pressing a button:
1. ZKE responds to pressed button only to
unlock a locked vehicle. Indicates the bat-
tery is between 2.6 - 2.2 volts. Replace bat-
tery.
2. No unlock of vehicle. Indicates battery is
below 2.2 volts. Replace battery.
FZV Key Test: Pressing the trunk release and lock buttons together activates the key test. If
the battery and FZV key EEPROM are “OK”, the LED will come ON for approximately 1 sec-
ond.
FZV Key Rechargeable Battery
From KL R, the battery inside the key head is charged inductively by the EWS ring antenna
via a coil antenna integrated in the key. The charging process is controlled by electronic
circuitry integrated in the key.
• The service life of a radio-control key used under normal conditions corresponds to the veh-
icle lifespan.
• If the FZV keys are not used (ie: stored in a drawer), the battery will be discharged after
approx. 1.5 years.
• The time required to fully charge a discharged battery is approx. 30 hours.
• The remote control can be operated about 15 times after a charging period of approx. 30
minutes (driving time).
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Central Body Electronics ZKE III

Power Windows/Sunroof
Purpose of the System
The features of the power windows and sunroof system include:
• One-touch operation in both directions (up/
down) on all four windows.
• The cable design window regulator is used
for all windows.
• Anti-trap detection is through the use of the
pressure sensitive finger guard.
• The control of the front window motors is
carried out in the respective door modules.
• The control of the rear windows is carried
out in the GM III.
• The switch block/module on the driver’s
door panel controls all four windows and the
rear window lock out feature.
System Components
- with the Principle of Operation
The signals from the switch block pass through
the driver’s door via the P-Bus and on to the
GM III and passengers door module.
Each window switch has four positions.
Two for the standard mode of operation:
• Push to first detent and hold to raise/lower
the window (1).
Two for the one-touch mode:
• Push to second detent and quickly release
(quick strike) to automatically raise/lower
the window (2).
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Central Body Electronics ZKE III
1
2
Rear Windows
Lock Out
Switch

Workshop Hints
SHD Self Diagnosis
The SHD monitors operation and stores fault codes if a defect is determined. The SHD
monitors the following conditions:
• SHD motor relays:The relays are checked for sticking contacts (plausibility) and non
functional contacts.
• Hall effect position sensors:The SHD must detect a pulse frequency from the hall
effect sensor(s) during operation.
• Sunroof Switch: The SHD monitors the signal plausibility of the coded signaling from
the sunroof switch.
Sunroof Fault Response Characteristics
If a fault occurs with any of these functions, the SHD responds as follows:
• Overrides the end run detection.
• Switches the motor off if the relay contacts stick for more than 500 ms.
• Switches the motor off if pulses are not received.
Emergency Operation of the Sunroof
If the sunroof motor does not respond to the switch signals, the hex key in the trunk lid tool
kit is used to manually turn the motor shaft drive.
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Central Body Electronics ZKE III

System Components
Door Contacts: As mentioned in the Central Locking Section, the existing door contacts
opened/closed are also an input for the interior lighting function. The E53 uses the Hall
effect sensors for the purpose of monitoring door open/closed status (located directly
behind the rotary latch plate encased in the actuator). The sensor is activated by the rotary
latch plate's position.
• Door closed, the rotary latch plate is in the latched position. Current flow through the
hall sensor is < 5 mA.
• Door open, the rotary latch plate is in the open position. Current flow through the hall
sensor is > 12 mA.
A change in current flow informs the General module when a door is opened or closed.
Front Seat Interior/Map Light Unit:The overhead front seat interior light unit contains a
single main interior light. The light is controlled by the GM automatically or by momentarily
pressing interior light switch located on the light assembly.
The switch provides a momentary ground signal that the GM recognizes as a request to
either turn the light on (if off) or turn the light off (if on).
If the switch is held for more than 3 seconds, the
GM interprets the continuous ground signal as a
request to turn the interior light circuit off for the
Workshop Mode
.
The workshop mode is stored in memory and
will not come back on even if the GM is removed
from it's power supply and reconnected. The
switch must be pressed to turn the lights back
on.
There are two reading/map lights also located in the assembly. Each map light is mechan-
ically controlled by depressing the corresponding on/off switch. The power supply for the
map lights is supplied by the GM through the Consumer Cut Off circuit.
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Central Body Electronics ZKE III

Rear Seat Interior/Reading Light Units: In
each C pillar trim panel is an interior/reading light
unit.
These units each contain an interior light that is
controlled with the front interior light and a
mechanically switched reading light on the con-
sumer cut off circuit.
Front Footwell Lights: In each front footwell,
there is also a courtesy light. These lights are
only operated when the GM provides power to
the interior lighting circuit.
On E38 and E53 the doors also contain courtesy
lights at the lower edge of the door panel (1).
Door Warning Lights (E38): The additional
“red” warning lights are installed in the edge of
the doors (2). These lights are illuminated when
the doors are opened.
Illuminated Transmission Shift Indicator
(E38): The E38 uses a microprocessor for dis-
playing the shifter position in the center console.
The processor receives shift position signals
from a console mounted range switch. The
processor illuminates the LED corresponding to
the position of the range selector.
The park position LED will remain “on” after the
ignition is switched off and stay on until the GM
goes into the “sleep” mode.
Soft Lighting Feature: The GM provides progressive voltage (up to 12v) providing the soft
on feature
to the interior lighting circuit when the interior lights are required. The GM grad-
ually reduces the full 12 volt power supply providing soft off
when interior light deactivation
is required.
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Central Body Electronics ZKE III
Park
Position
LED