coding BMW 525I 1998 E39 Central Body Electronics ZKE Manual

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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
12520101.eps

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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

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Seat/Mirror/Steering Column Memory
Purpose of the System
The front seats, outside rearview mirrors and steering column (if equipped) positions are
electrically adjustable. The “customized” adjustment positions can be memorized and
stored for three diferent users and recalled back to the individual positions (with the excep-
tion of the passenger seat - not in memory).
The basic features of seat/mirror/steering column operation, as well as the memory posi-
tions is integrated into the ZKE III system.
• Seat/Steering Column Memory
Module (PM SM).
• Driver’s Door Switchblock Mod-
ule (PM FT/SB - early E38 was
separate).
• Passenger’s Door Module (PM
BT - E53 combined with window
switch).
• General Module (GM III).
• 3 Position Memory Switch.
• Seat Switch.
• Steering Column Switch.
• Seat/Steering Column/Mirror
Motors.
The Seat/Steering Column Memory Module communicates with the DISplus or MoDiC for
diagnosis and Vehicle Memory encoding.
58
Central Body Electronics ZKE III
System Components: Inputs - Processing - Outputs
E38/E39 Shown