
Remote (Keyless) Entry FZV
Purpose of the System
The Remote Entry System offers the following:
• Locking/unlocking of doors, luggage compartment (tailgate), fuel filler lid.
• Selective unlocking of driver’s door (same as with key in the lock cylinder).
• Arming/disarming of DWA alarm system.
• Remote unlocking of the trunk (tailgate) only.
• Comfort opening of windows and sunroof.
• Interior lighting activation (search mode).
• Panic mode alarm activation.
• Changing code signals - coded signals from transmitter change with every operation.
• Automatic correction for up to 1000 erroneous activation signals.
• Transmitter initialization procedure - including up to four key operation and Key Memory.
• Replacement batteries.
• Low transmitter battery in vehicles equipped with Check Control. 
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The  Remote  Entry  System  incorporated  minor  changes  since  the  original  introduction
which includes:
• The control electronics are incorporated into the GM III.
• The antenna is incorporated into the rear window lower heater grid. 
• The  remote  key  receiver  is  installed  in  the  left  “C”  pillar.  The  receiver  produces  a  digital
signal based on the transmitter command and sends it to the GM for processing. The GM
then  carries  out  all  remote  entry  operations  either  directly  or  through  the  door  modules
for the front doors. The frequency at which the key transmits the radio signal to the ant- 
enna amplifier is 315 MHz.
Vehicle/Key Memory 
The Vehicle/Key Memory feature provides the flexibility of allowing the owner to customize
certain functions of select vehicle systems and automatically identifies users of the vehicle
by a key identification signal provided by the remote keyless entry system (FZV).
Vehicle & Key memory is marketed as a combined feature but is actually two separate func-
tions of the select vehicle control systems.
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A
IHKA
K-BUSKEY #1
KEY #2
KEY #3
KEY #4
GMV
SM
  Adjust Setting of Seat
For Key #1   IHKA Features Key #1
Being Used
KEY 4
KEY 3
KEY 2
KEY 1
KEY 1
- Selective Unlocking
- Automatic Locking
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System Components
Interior  Sensor  FIS  (up  to  99  MY): The  interior  sensor  is  mounted  in  the  center  of  the
headliner panel. Due to the design of the vehicles interior, the sensor is uni-directional and
must be installed in the proper direction to ensure proper operation of the system.
When the alarm system is armed, the sensor emits electromagnetic waves at a frequency
of  2.45  GHz.  As  long  as  nothing  is  moving  in  the  vehicle,  the  waves  as  bounced  back  to
the sensor at the same frequency. The sensor monitors these bounced back waves as an
indication that nothing is disturbed within the vehicle.
If  a  foreign  object  enters  the  vehicle,  the  frequency  of  the  bounced  back  signal  changes.
The sensor monitors the changed frequency and triggers the alarm.
Every  time  the  DWA  system  is  armed,  the
sensor  adapts  to  what  ever  objects  might  be
stationary in the interior. 
This  allows  packages  or  objects  to  be  left
inside  the  car  without  effecting  the  operation
of  the  system.  The  sensitivity  of  the  sensor  is
set so that the moving object must be at least
as  large  as  a  bumble  bee.  This  prevents  a
false  alarm  from  occurring  from  small  insects
that might be caught in the vehicle.
The FIS is switched OFF when the vehicle is locked two times within ten seconds. The LED
will flash one time for confirmation. This allows the sensor to be switched OFF to avoid false
alarms when the windows are left open for venting.
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Interior Sensor UIS (after 99 MY):Similar to the FIS, the UIS monitors the vehicle interi-
or for motion. The UIS uses ultrasonic sound wavs instead of microwaves (less suceptable
to magnetic interference). The UIS is a combined transmitter and receiver.
The interior sensor is mounted in the center of the headliner panel. Due to the design of the
vehicles  interior,  the  sensor  is  uni-directional  and  must  be  installed  in  the  proper  direction
to ensure proper operation of the system (trim cover ensures directional installation).
Every  time  the  DWA  system  is  armed  (signal  STDWA),  the  sensor  adapts  to  what  ever
objects  might  be  stationary  in  the  interior.  The  sensor  emits  ultra  sonic  waves  in  a  pro-
grammed timed cycle. It receives echos of the emitted waves.  
The UIS amplifies the received sound wave signals and compares them with the transmit-
ted  waves.  The  UIS  also  checks  the  incoming  echos  for  background  hiss  (wind  noise
through a partially open window) and adapts for this.
• If the echos are consistently similar, no movement is detected.
• If  the  echos  are  altered,  (inconsistent),  the  UIS  determines  motion  in  the  interior  com-
partment. 
If motion is detected, the UIS changes to a constant cycle and the echo is compared again.
If the inconsistency is still present the UIS sends the activate siren signal (INRS) to the GM.
The UIS is switched OFF when the vehicle is locked two times within ten seconds. The LED
will flash one time for confirmation. This allows the sensor to be switched OFF to avoid false
alarms when the windows are left open for venting.
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•  Signal "NG"; switched ground output signal provided to the GM. The signal is used for
two purposes,
1. As  a  momentary  acknowledgment  that  the  tilt  sensor  received  STDWA  and  is  cur-
rently monitoring the vehicle angle.
2. If the tilt sensor detects a change in the vehicle's angle when DWA is armed, signal
NG is switched to inform the GM to activate the siren. 
When  the  tilt  sensor  receives  the  STDWA  signal  from  the  GM  it  memorizes  the  vehicle's
parked  angle.  The  angle  of  the  vehicle  is  monitored  by  the  solid  state  electronics.  Once
armed,  if  the  angle  changes,  the  tilt  sensor  provides  a  switched  ground  signal  to  the  GM
to activate DWA.  
As with the interior sensor, the tilt sensor is also switched OFF when the vehicle is locked
two times within ten seconds. The LED will flash one time for confirmation. This allows the
sensor to be switched OFF for transportation purposes.
Glass Breakage Sensors (Early E38 - before FIS Sensor): The door windows (includ-
ing  the  rear  quarter  glass  wire  loop)  are  monitored  by  inductive  sensors  mounted  on  the
inside of the door behind the trim panel. A closed window is recognized by a magnetic plate
on the glass lining up with the sensor. 
If the glass is broken, the plate falls away and the signal from the sensor changes and the
GM will activate the alarm.
Alarm  Siren: The  alarm  siren  is  mounted  in  the  rear  wheel  well,  behind  the  inner  wheel
housing cover (early E38 used an alarm horn). The E53 alarm siren is located in the left side
of the engine compartment.
The  siren  contains  electronic  circuitry  for  producing  the  warn-
ing tone when the alarm is triggered. The siren also contains a
rechargeable battery that is used to power the siren when the
alarm is triggered.  
The rechargeable battery will allow the siren to sound if it or the
vehicle’s  battery  is  disconnected.  The  siren  battery  is
recharged, from the vehicle’s battery, when the alarm is not in
the armed state.
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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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1
2
Rear Windows
Lock Out
Switch 

All window operations signals are digital inputs to the door module and GM III.
• Comfort closing/opening of the windows from the driver’s  lock cylinder. The remote key
provides opening only.
• When the ignition key is in accessory or “on” position press the switch to open or close
the  windows.  Window  operation  is  possible  with  the  ignition  switched  off  until  a  front
door is opened or 16 minutes (maximum) has elapsed.
• Window load switching is through relays. The front window control relays are located in
the door modules, the rear window relays are in the GM III. The GM III monitors the cur-
rent draw for end limit position. The maximum run time for the window motors is limit-
ed to 6 seconds in the one-touch mode. This allows the motors to be switched off if the
end limit load sensing fails.
E53 Style Window Switches:The E53 power window switch design is a push - pull type
switch. Each switch provides the GM with the coded ground signaling strategy as previous
two wire switches.
Pushing a switch to the first detent and holding
provides
a  single  ground  signal  on  one  wire
requesting  the  GM  to  operate  the  window
motor in the down direction. 
When  released,  the  ground  signal  is  removed
and the window motor stops.
Momentarily pushing the switch to the second
detent and releasing provides
an  additional
ground  signal  on  the  second  wire  requesting
the  “one  touch  mode”,  operating  the  window
motor automatically. 
The motor runs the window down until it reach-
es the end stop.  
The  switch  functions  in  the  same  manner  for
the  upward  run  of  the  window  motor  but  the
ground signal sequencing is reversed.
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Rear  Window  Child  Lockout  Switch:  The  rear  window  child  lockout  switch  is  incorpo-
rated in the driver's side window switch block. It provides a constant ground signal to the
GM preventing the windows from being operated from the rear door switches.
The lockout switch ground signal is overridden by the GM if the MRS crash signal is acti-
vated (MRS III equipped vehicles).
Window Anti-Trap Detection: Each pressure guard at the top edge of each door frame
consists  of  two  contact  strips  that  close  when  subjected  to  pressure.  This  provides  anti-
trap for the full travel of the window.  
When the contact strips close, the window will reverse direction. The contact strip does not
require that the anti-trap feature be initialized prior to operation.
The finger guard has a resistance of 1.2 KOhm and it is monitored for open circuits. Faults
with the anti-trap system require that the window switch be held to close the window.
The example shown represents the driver’s door window control and monitoring carried out
by the Driver’s Door Switchblock Module (PM- FT/ SB).  
The  passenger  door  window  is  controlled  and  monitored  by  the  Passenger  door  module
(PM-BT)  and  the  rear  door  windows  are  both  controlled  and  monitored  by  the  General
Module.
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