
10
Central Body Electronics ZKE III
Blocking Protection = Return
Contact Signal must be
present every 16 seconds
or motor will be deactivated >98 MY
1.49v-3.5v
Headlight  Washing  (if  equipped):When  the  headlights  are  on,  the  headlight  washer
pump is activated with the first activation of the windshield washer pump. It is only activat-
ed again after five succesive windshield washer cycles during the same ignition key on cycle
(rest  function).  The  GM  recognises  headlights  on  via  K-Bus  signalling.  The  GM  provides  a
ground on the headlight washer relay control circuit providing pump operation. The head-
light washer pump is located on the side of the washer fluid reservoir.
System Components:   Inputs - Processing - Outputs
12510122.eps
E53 Shown 

Rear  Window  Wiper/Washer  System  (E39  Sport  Wagon  and  E53): The  system  is
included in the scope of ZKE however is not controlled directly by the GM. The control elec-
tronics are integrated into the rear wiper motor assembly. The control electronics contains
two hall sensors, one for monitoring park position and other for the end stop, or to signal
reverse  direction  of  the  wiper  motor.  The  control  electronics  are  connected  to  the  vehicle
electrical system via a single seven pin connector.
The  rear  wiper  system  is  operator  controlled
through the wiper stalk switch providing the fol-
lowing functions:
• Intermittent rear window wiping
• Programmed rear window wiping interval
• Operation of the rear window washer
Pressing the wiper stalk forward to the first detent activates the rear wiper in the intermit-
tent mode
. The timed interval is approximately 7-12 seconds. The full sweep and park posi-
tions  are  recognized  by  the  two  hall  sensors  on  the  motor  gear  assembly.  If  the  wiper  is
switched OFF, the wiper blade will return to the park position.
The programmed wiper interval procedure is as follows:
• Briefly switch the rear wiper ON/OFF
• Wait the desired interval time
• Switch the rear wiper ON again
• The OFF time will be the programmed interval - up to approx. 30 seconds
Rear window washing is activated by pressing the wiper stalk switch to the full forward
position.
The washer pump operates followed by two full wiping cycles. The wipers will then
switch to the intermittent wiping mode. Additionally, the system automatically controls the
following safety and convenience features:
• Wiper interrupt with the rear glass opened
• Wiping interrupt with a blocked wiper arm
• Continuous wiping when the vehicle is shifted into reverse 
When the transmission is shifted into reverse, the wiper will switch to continuous operation
until the vehicle is shifted out of reverse. This signal (high) is provided by the LCM III when
it activates the back up lights.
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Central Body Electronics ZKE III
12510111.eps 

Luggage Comparment Remote Unlock: The luggage com-
parment  can  be  opened  from  inside  the  vehicle  with  the
remote release button. This feature is also functions when the
doors are locked from the central button. 
The  GM  will  disregard  the  remote  release  button  input  when
the  luggage  comparment  is  mechanically  locked  with  the
Master Key (valet setting). 
The  GM  will  also  disregard  the  release  input  if  the  vehicle
speed is > 4 MPH.
The  E53  remote  release  button  is  located  in  the  center  con-
sole. This input will release the rear liftgate following the same
criteria stated above.
Crash Signalling
The Multiple Restraint System (MRS) control module provides a switched signal to the GM
in the event of an accident. This signal was previously provided by the crash sensor locat-
ed in the left front kick panel (< 9/96 MY). 
The signal is an output function of the MRS control module and becomes active when MRS
determines  a  crash  has  occurred.  The  GM  unlocks  the  vehicle,  switches  on  the  interior
lights and flashes the exterior lights when this signal is active.
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Central Body Electronics ZKE III
12520123.eps
12520124.eps
12520125.eps 

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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Central Body Electronics ZKE III
615200102.eps 

Principle of Operation
DWA Arming/Disarming
• The DWA is armed every time the vehicle is locked from the outside with the door lock
cylinder or FZV key. 
• The  DWA  LED  flashes  as  an  acknowledgment  along  with  the  exterior  lights  and  a
momentary chirp from the siren.
• The GM monitors all required input signals for closed status (door closed, luggage com-
partment  closed,  etc.)  The  inputs  must  be  in  a  closed  status  for  a  minimum  of  3  sec-
onds  for  the  GM  to  include  them  as  an  activation  component.  If  after  3  seconds  any
input signal not in the closed status is excluded (this is acknowledged by the DWA LED)
preventing false alarm activations. The hood switch can be “lifted” to the service posi-
tion to test the alarm with the hood open.
• If the DWA is armed a second time within 10 seconds, the tilt sensor and interior pro-
tection  sensor  are  excluded  as  alarm  activation  components.  This  function  is  useful  if
the vehicle is transported on a train or flat bed truck to prevent false alarm activations.
• While armed, the trunk can be opened with out the alarm being triggered as follows:
- If opened with the trunk remote button via the FZV, the GM prevents the alarm from
activating. (This feature is customizable under the Car Memory function).
- If  opened  with  the  key  at  the  trunk  lock  cylinder  the  trunk  key  position  switch  sig-
nals the GM and in the same manner prevents the alarm from activating.
In either case, when the trunk is returned to the closed position, it is no longer con-
sidered as an activation signal. 
Panic Mode Operation: When the trunk button is pressed and held, the GM is signaled
to activate the siren for the Panic Mode. The panic mode is function with either an armed
or disarmed DWA system.
Emergency Disarming: Emergency disarming occurs automatically if a key is used to turn
the ignition switch on and the EWS accepts it. The EWS signals the GM to unlock the doors
and deactivate the DWA.
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Central Body Electronics ZKE III 

Alarm Indication
When the alarm is triggered, the siren will sound for 30 seconds. At the same time the low
beam headlights (high beams on Xenon equipped vehicles) and four way flashers for 5 min-
utes. The GM signals the LCM via the bus system to flash the lights.
Following  an  alarm  activation,  the  system  will  reset  and  activate  again  if  further  tampering
occurs.
DWA LED Status:
Notes: _______________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
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Central Body Electronics ZKE III
DWA STATUS DWA LED CONDITION
Disarmed OFF
Armed Continual slow flash
Armed with one or more monitored Rapid flash for 10 seconds,
inputs not in closed position then continual slow flash.
(ie: trunk not fully closed, etc)
Alarm activated Rapid flash for 5 minutes,
then continual slow flash.
Rearmed in less then 10 seconds. ON for 1 second
Disarmed after activated alarm Rapid flash for 10 seconds, 
then OFF. 

Interior Lighting
Purpose of the System
The GM controls the interior lighting automatical-
ly  with  the  status  change  of  several  monitored
inputs.  The  lighting  can  also  be  manually  con-
trolled using the interior light switch.
In addition to the various time controls, the inte-
rior lights are also subject to the 16 minute shut
down of the GM (consumer protection).
Principle of Operation
The interior light switch is a push button switch that will carry out the opposite command
of the current status of the lights. (ie: if the interior lights are currently on, pushing the but-
ton will switch the lights off.)
• If the interior lights are switched “ON” by the button with the ignition switched ON, the
interior lights will remain on until they are switched off by the button.
• If the interior lights are switched “ON” when the ignition is switched OFF, the lights will
remain on for 16 minutes (consumer cutout).
• Pressing  the  interior  light  button  for  longer  than  three  seconds  will  switch  the  lights  to
continuous off. This feature is intended for workshop use.
Pressing the button again will
return the lights to the normal operational status.
•    Locking the vehicle from the outside will immediately switch off the interior lights.
The ON/OFF conditions for the interior lights in the automatic mode are as follows:
ON Conditions
• Door Open.
• Switching off ignition after exterior  
lights have been switched off.
• MRS Control Module crash input.
• Unlocking with FZV or pressing FZV
lock button when the vehicle is
already locked (interior search fution).
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Central Body Electronics ZKE III
OFF Conditions
• All doors closed with ignition on.
• All doors closed with ignition off after 20  
seconds.
• 20 seconds after switching off ignition with 
lights off.
• 8 seconds after remote control activation.
• 16 minutes with door(s) open.
• When doors are locked. 

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