1999 BMW 528i glove box

4
Central Body Electronics ZKE III
System Components
General Module (GM): The GM is reponsible
for the operation and central coordination of
body electronics. The GM is a micro-computer
that is the central component (heart) of the
Central Body Electronics. The GM is located be-
hind the glove box.
The main objectives for using the GM are:
The GM requires inputcommands to perform
Central Body Electronics functions. The inputs
are supplied by digital switched signals such
as:
• Trunk Lock Microswitch - supplies voltage (KL
30) to the GM when switched. A path to gro-
und is provided by the GM (internally). The
GM monitors the switched input voltage.
• Central Lock Button - supplies a ground cir-
cuit to the GM when switched. The GM sup-
plies and monitors a reference voltage (5v)
that is “pulled” low when the switched gro-
und path is provided.
The GM processesthe input information and
contains “coded” instructions that allow a spe-
cific output control of functions.
The GM will produce outputfunctions using
internal transistors to switch current flow (pro-
viding voltage or ground) through circuits and
actuators. Actuators are the final controlling
devices used by the GM to operate or control
various output functions such as relays and
motors.
• Increase Overall Reliability
• Centralize Electronic Systems
• Decrease Assembly and Service Repairs
• Centralized Diagnosis of all ZKE Components
• Individualization of Features (Coding)
CENTRAL LOCK BUTTONCENTRAL LOCK BUTTON
TRUNK LOCK BUTTONTRUNK LOCK BUTTON
KL 30KL 30
TRUNK LOCK MICROSWITCHTRUNK LOCK MICROSWITCHSignal Monitor
5v
Supply/
Monitor
GM
FUEL
FILLER
FLAP
RELAY
Transistors
GM
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5
Central Body Electronics ZKE III
The ZKE III system offers an overall reduction in vehicle wiring particularly in the areas sub-
ject to wear from movement such as doors, seats and the steering column. To accomplish
this, the “P- Bus” is used to interface (signaling) with peripheral modules over a single wire.
The ZKE III modular system consisting of the following components:
• General Module III = Main controller for ZKE functions
• PM - SB/FT = Driver’s door switch block and door module
• PM - BT = Passenger’s door module
• PM - SHD =Sunroof module
•PM - SM =Seat/Mirror/Steering Column memory module
• AIC = Rain Sensor (if equipped)
All modules communicate through the P-Bus and GM III onto the K-Bus for diagnosis.
PM-FT/SB
PM-SMPM-BT
PM-SHD
P-BUS
K-BUS
Driver's Door
Switchblock/
ModuleDriver's Door
Switchblock/
Module
Seat Memory
ModuleSeat Memory
Module
Passenger's
Door ModulePassenger's
Door Module
Sunroof
ModuleSunroof
Module
GM IIIFBZVFBZVDWADWA
FBZV
RECEIVER
MODULE
GM III MODULE
LOCATED IN CARRIER
FORWARD OF GLOVE BOX
Separate
Switch and
Module < 96
E38 on K-Bus
>99 MY
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7
Central Body Electronics ZKE III
Power Distribution
The power distribution box for the
E38 is incorporated in the Electr-
onics box in the engine compart-
ment.
The power distribution box for the
E39 and E53 is inside the vehicle.
The main fuse box is located
inside the glove box above a
hinged panel.
A “pull out” fuse designation card
is also located in the fusebox. This
notes:
• Fuse value in amps
• Location
• Circuit listing by fuse
The placement of the power distribution box is
close to the main electronics carrier behind
the glove box. The modules/relays located in
the electronics carrier include (examples):
• General Module III (GM III)
• Drive away protection (EWS II)
• Anti-lock Brake (ABS/ASC+T)
• Light Check Module (LCM) - behind right kick
panel
• Overload protection relay module
An auxiliary fuse block is located in the trunk
above the battery. In addition to fuses, the
auxiliary fuse block also contains relays (exam-
ples):
• Fuel filler flap lock motor relay
• Fuel pump relay (some vehicles)
• Rear defroster relay
• Unloader relay
FUSE
DESIGNATION
CARDFUSE BOX DROPS
DOWN AFTER TURNING
TWO THUMB SCREWS
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• The luggage compartment can be manually
locked with a “Master Key” and leaving the
lock cylinder in the horizontal position which
prevents opening by any other method (sec-
ured for valet).
The luggage compartment release button in-
side the vehicle will also be ignored by the GM.
Prior to 2000 MY the vehicle could be locked/
unlocked using the luggage compartment lock
cylinder.
• The glove box has a lock cylinder to secure the
contents by manual locking with a “Master
Key” and leaving the lock cylinder in the hori-
zontal position which prevents opening by any
other method (secured for valet).
• The E38 has a lever behind the glove box han
dle which permits locking the glove box with-
out a key. Opening still requires a key.
The valet key is not mechanically capable of
entering either of these lock cylinders.
• The Fuel Filler Flap mechanical release is found
in the right side of the luggage compartment.
The “pull tether” is behind the button as shown
on the right.
Note: Continuous operation of locking/unlocking will cause a timed arrest of the
locking system. When activated, the timed arrest lasts for 2 minutes (or recycle
the ignition KL15). The “crash” signal will override the timed arrest and unlock the
vehicle.
19
Central Body Electronics ZKE III
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12520121.jpg
51500002.tiff

Exterior Door Handle Lighting: The Visual
Entry Aid Control Module is located in the elec-
trical carrier forward of the glovebox.
To control the system, the Visual Entry Aid con-
trol module requires:
• KL 30
• KL 15
• KL 31
• Interior Light control signal (GM Output)
The GM controls the soft on/off feature of the vehicle interior lights by a pulse width mod-
ulated control signal. This signal is also an input to the Visual Entry Aid control module
which requests simultaneously control (soft on/off) each exterior door light source.
Light Source Modules: Mounted in each door
are the light source modules.
The light source modules are made up of the
housing, halogen bulb and reflector. The reflec-
tor holds the bulb and focus the bulbs light into
the housing.
The bulbs are are available for individual replace-
ment.
56
Central Body Electronics ZKE III
CONTROL MODULE
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General Functions of ZKE III
Consumer Cut Off
The Consumer Cut Off function interrupts battery voltage to circuits preventing inadvertent
battery drain if one of these consumers were to remain activated. Circuits controlled by
consumer cut off will be switched off as the GM enters into the sleep mode.
For example, the interior lights are connected to the consumer cut out circuit (KL 30) and
can remain on if one of the control switches are left on. The consumer cut off will deacti-
vate KL 30 to the interior lighting after 16 minutes (or with the DISplus/MoDIC).
The following circuits are con-
trolled by consumer cut off:
• Map/Reading Lights
• Glove Box/Luggage Compart-
ment Lights
• Transmission Range Indicator
Light
• Overload Protection Relay for
- Power Seat Motors
- Steering Column Motors
Overload Protection
The seat and steering column motors receive
operating power through the consumer cutoff/
overload protection relay module. The consumer
cutoff signal from the GM signals the relay to
maintain operating power to the consumers.
If the relay module detects an increase in amper-
age (overload) the relay will open. The relay mod-
ule (K-72) is located in the electrical carrier
behind the glove box. The relay is reset by
switching the ignition “off” for 16 minutes, dis-
connecting the relay or the DISplus/ MoDIC.
75
Central Body Electronics ZKE III
E38 Shown
Overload
Protection Relay
Module