Page 31 of 80

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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        Page 33 of 80

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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615200102.eps 
     
        
        Page 40 of 80

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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        Page 41 of 80

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. 
     
        
        Page 50 of 80
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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        Page 76 of 80

Sleep Mode
To lower the constant battery draw when the vehicle is parked, the complete ZKE system
will  go  into  the  “Sleep  Mode”  16  minutes  after  the  ignition  has  been  switched  off  and  no
further ZKE function is active. 
For example, the approximate E39 (528i) Battery draw is: 
• Ignition switch off = approx 750 mA.
• One minute after = approx. 560 mA.
•  After 16 minutes (sleep mode) = approx. 18 mA.
All modules in the ZKE system will go into the sleep mode. The P-Bus remains active, how-
ever no data transfer takes place until a wake-up request is received. The general module,
door  modules  or  keyless  remote  module  can  wake  the  system  up  and  put  the  ZKE  back
on line. The K-Bus is active (high) in the sleep mode.
Sleep Mode Criteria:
KL R, KL 15 OFF and no further function activated for 16 minutes.
Wake Up Criteria:
KL R or 15 “ON” or a change in one of the signals listed below.
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Central Body Electronics ZKE III
SIGNAL ACTIVITY ORIGINATING
MODULE
K-BUS High General Module
Door jamb switches (possibility of 4) Low “
Trunk lid lock cylinder microswitch High “
Trunk lid pushbutton microswitch Low “
Interior Trunk lid pushbutton microswitch Low “
Central locking button Low “
Hood microswitch Low “
Trunk Lid microswitch Low “
Interior light switch Low “
FIS sensor Low “
Tilt Alarm sensor Low “
FBZV operational signal High FBZV Module 
Driver’s door lock microswitch      - (lock) High PM-FT/SB
“ “ “ “ - (unlock) High “
Passenger door lock microswitch - (lock) High PM-BT
“ “ “ “ - (unlock) High “