turn signal BMW X5 2000 E53 Central Body Electronics Workshop Manual
Page 9 of 64
REAR WINDOW WIPER/WASHER SYSTEM
The  tailgate  window  wiper/washer  system  is  included  in  the  scope  of  ZKE  however  is  not
controlled  directly  by  the  GM.      The  control  electronics  are  integrated  into  the  rear  wiper
motor  assembly.    It  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  rear  wiper  system  is  operator  controlled
through  the  wiper  stalk  switch  providing  the
following 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
intermittent mode. 
The default timed interval is approximately 12 seconds. The full sweep and park positions
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  identical  to  the  E39  sport  wagon;  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.
When the transmission is shifted into reverse, the wiper will switch to continuous operation
until the vehicle is shifted out of reverse. This high signal is provided by the LCM III when it
activates the back up lights.
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THEORY OF OPERATION:
The  optical  infra  red  portion  of  the  sensor  operates  by  the  principle  of  refraction  (bending
of  a  light  ray).    The  rain  sensor  control  module  activates  the  emitter  diode  which  sends  a
beam  of  infra  red  light  through  the  windshield  on  an  angle.  The  set  angle  is  important
because it provides the beam with a calculated reflective path back to the detector diode.
The  beam  is  reflected  back  into  the  windshield  due  to  the  density  difference  of  the  glass
compared with the ambient air on the outside surface of the glass.  When the windshield is
clean (no rain drops, moisture or dirt) the detector diode receives 100% of the infra red light
that the was sent by the emitter.   With this condition, the rain sensor evaluation electronics
determines the windshield is free of rain drops. 
The density of water is closer to that of glass than air.   When rain starts to accumulate in
the sensor monitoring area, it causes part of the infra red beam to extend past the outside
surface of the glass and into the rain drop.   When this occurs, the beam is refracted and
only part of the beam returns to the detector diode.
The  rain  sensor  evaluation
electronics  determines  the
windshield  has  a  few  rain  drops
(or dirt) on it.  
The  intensity  of  the  returned  infra  red  beam  diminishes  proportionally  with  an  increase  of
water  droplets.    The  rain  sensor  control  module  generates  a  signal  proportionate  to  the
amount of rain on the windshield and broadcasts it to the GM III via the K bus.
The GM III activates the intermittent wipe cycle if the windshield wiper stalk switch is in the
intermittent  position.    It  also  adjusts  the  frequency  of  wiping  the  windshield  depending  on
the four position thumb wheel.
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RAIN SENSOR FUNCTION:
The rain sensor is online as soon as it receives KL R operating power. 
• When  the  windshield  wiper  stalk  switch  is  placed  in  the  intermittent  position  the  GM
signals  the  rain  sensor  control  module  via  the  K  Bus  of  the  request  for  intermittent
wiping and the position of the knurled wheel (sensitivity).  
• As  an  acknowledgement,  the  rain  sensor  sends  a  command  via  the  K  Bus  to  activate
the  wiper  motor.    If  more  than  12  seconds  pass  before  the  GM  receives  the
acknowledgement,  the  GM  concludes  the  rain  sensor  has  a  defect  and  operates  the
intermittent  wipe  function  as  a  system  not  equipped  with  a  rain  sensor.    The  wiper
intermittent cycling is based solely on the knurled wheel setting.
• The rain sensor continuously monitors the windshield for rain accumulation and signals
the GM to activate the wipers based on the knurled wheel position and how fast the rain
accumulates on the windshield.   
• The  knurled  wheel  position  signal  (1-4)  via  the  K  bus  informs  the  rain  sensor  of  the
selected level of sensitivity.  
- Position 1 (least sensitive) delays the wiper activation signal.
- Position 4 (most sensitive) sends the wiper activation signal to the GM sooner.
• When the wiper motor park contacts signal the GM of the wiper arm position, the signal
is simultaneously sent to the rain sensor as an indication that the windshield has been
cleared  of  water  drops  and  causes  the  rain  sensor  to  reset  the  sensitivity  delay  timer
back to 0.
• If night time driving is detected via the integral photocell, the sensitivity to water droplets
is increased causing a shorter delay than day time driving.
• Depending on the intensity of the rain the wipers will be operated continuously as if set
in  the  normal  wiper  stalk  switch  position  regardless  of  the  knurled  wheel  setting.   For
this reason, the vehicle speed signal on the K bus is not utilized on rain sensor equipped
wiper systems.
• If the ignition switch is turned off with the wiper switch in the intermittent position,  the
rain sensor will only become active after the ignition is switched back on and one of the
following occurs:
- The stalk switch is moved from the intermittent position and then back.
- The knurled wheel setting is adjusted.
- or the wash function is activated.
The  reasoning  behind  this  switching  strategy  is  to  have  the  driver  make  a  conscious
decision to activate the system themselves.   
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DOOR LOCK ACTUATORS
The  actuators  are  sealed,  self  contained  units  with  no
replaceable parts.  The door lock actuators use hall effect
sensors to provide:
• Door lock key position (driver’s door only),
• Door open/closed status.
The driver’s door lock provides the following signals to
the driver’s door switchblock module (PM-FT/SB):
• Lock / Unlock,
• DWA arm/disarm 
• Convenience closing and opening signals.
DOOR LOCK POSITION HALL
SENSORS
The  Drivers  door  switchblock
module monitors these key positions
over  two  wires.    The  signals  are
generated by two hall effect sensors
(Hall  Sensor  1  &  2)  located  in  the
actuator. 
When  the  key  is  turned,  a  plastic
cylinder  in  the  lock  actuator  is
simultaneously  rotated  by  the  lock
tumbler extension rod.  
A  magnet  is  incorporated  in  the
plastic  cylinder,  which  when  rotated
changes  the  magnetic  influence  on
the hall sensors.
The  presence  of  a  magnet  in  close
proximity  to  the  sensing  surface  of
either  hall  sensor  creates  a  coded
input over the two wires that the GM
uses to determine the key position.
• Magnet in front of sensor, current flow through the sensor is <5 mA (0). 
• Magnet rotated away from sensor, current flow through the sensor is >12 mA (1).
Hall sensor 1 & 2 are not included in the front passenger door or rear door actuators.
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NEUTRAL
- 0 -
MANUAL
LOCK
HALL SENSOR 1
MANUAL
UNLOCK
• DOUBLE LOCK
 DWA ARMED
 CONVENIENCE
CLOSING (hold
until activated). UNLOCK
 DWA DISARMED
 CONVENIENCE
OPENING (hold
until activated).
HALL
SENSOR 2
TUMBLER
EXTENSION ROD
PLASTIC CYLINDER WITH ASYMMETRICAL MAGNET
(Shown in the Lock Position)    
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CENTRAL LOCKING BUTTON
The  central  lock  button  in  the  center  console
provides a momentary ground input signal to the
GM. 
• This input initiates a single lock for each  door
and the trunk. 
• The  fuel  filler  flap  remains  unlocked  for
refueling purposes.  
• If  a  door  is  manually  opened  while  centrally
locked, the remaining doors stay locked.  
The opened door can be re-locked when closed by manually locking or pushing the central
button twice.  This allows the locks of the remaining doors to be re-synchronized again.
As an additional safety feature, the central lock button input also unlocks a double locked
system.    Pressing  the  button  returns  the  system  to  central  lock  (single)  position,  allowing
the doors to be opened when the interior door handles are opened twice.  This feature was
also added to other ZKE systems during the 1999 model year.
CRASH SIGNALLING
The  Multiple  Restraint  System  (MRS  III)  provides  a  switched  signal  to  the  GM  in  the  event
of an accident.    The signal is an output function of the MRS control module and becomes
active when MRS determines a crash has occurred.  
When  active,  the  GM  unlocks  the  door  lock  actuators,  switches  on  the  interior  lights  and
signals the LCM III via the K bus to activate the hazard warning flashers.
Once the crash signal is active, the GM will not respond to lock requests from the system
until the ignition switch is cycled or a front door is opened.  
Page 25 of 64
REMOTE KEY INITIALIZATION
The initialization of the  FZV  keys  is  required  to  establish  the  Lock/Unlock  signal
synchronization  with  the  GM.    The  initialization  procedure  provides  the  GM  with  a  key
identification number and a “rolling code” for each key.  If the initialization is not performed,
the GM will not respond to the key signals.
Up  to  4  remote  keys  can  be  initialized.    They  must  be  initialized  at  the  same  time.    Key
initialization is only possible with the vehicle unlocked.
Procedure:
1. Close all doors and have all keys available.
2. Using  key  number  1,  turn  the  ignition  switch
to KL R, then switch off within 5 seconds and
remove the first key.
3. Within  30  seconds  of  turning  the  ignition
switch  to  “off” Press and holdthe arrow
button.
4. While  holding  the  arrow  button, press and
release(“tap”) the roundel button three
timeswithin 10 seconds.
5. Release  both  buttons.    The  GM  will
immediately  lock  and  unlock  the  doors
signaling a successful initialization.
6. If  additional  keys  need  to  be  initialized  repeat
steps 3 - 5 within 30 seconds.
7. Switching the ignition to KL R completes the initialization.
SERVICE NOTE:The  key  memory  function  of  the  GM  responds  to  the  key  identification
number of each key.  If the keys are not initialized in the same order prior to initialization, the
key memory function activated by the keys will not be assigned correctly.
Always initialize the keys in the same order.
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Page 42 of 64
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SHD SELF DIAGNOSIS
The SHD monitors its 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 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 as on previous systems 
Page 43 of 64
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INTERIOR LIGHTING
The GM controls the interior lighting automatically with the status change of several moni-
tored inputs. The lighting can also be manually controlled using the interior light switch.
COMPONENTS
DOOR CONTACTS: The  door  lock  actuators  contain  a  hall  effect  sensor  for  the  purpose
of monitoring door open/closed status (hall sensor 3 in the driver's door actuator).   The hall
effect  sensor  is  located  directly  behind  the  rotary  latch  plate  encased  in  the  actuator.  The
sensor is activated by the rotary latch plate's position.  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/map  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 sig-
nal  as  a  request  to  turn  the  interior  light  circuit  off  for  the  Workshop  Mode  as  on  previous
systems.  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 it's corresponding  on/off switch.  The power supply for the
map lights is supplied by the GM through the Consumer Cut Off circuit.
Rear seat interior light unit:
In the center headliner is an additional interior/reading light unit.  This unit contains an inte-
rior light that is controlled with the front interior light and a mechanically switched  reading
light on the consumer cut off circuit.
Front footwell lights:
In  each  front  footwell,  there  is  also  a  courtesy  light.    These  lights  are  only  operated  when
the GM provides power to the interior lighting circuit. 
Page 45 of 64
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AUTOMATIC CONTROL FUNCTION
The  GM  provides  12  volts  (linear  application  providing  soft  on  feature)  to  the  interior  light-
ing circuit when the one of the following input signal statuses change:
•  Door contact hall sensor active (door opened)
•  An Unlock request from the driver's door key lock hall sensors are received.  This only
occurs if  the ignition switch is off.
•  An Unlock request is from the FZV keyless entry system is received via the K bus. This
only occurs if the ignition switch is off as well.
•  The ignition switch is switched off and the vehicle exterior lights (LCM III) have been on
for a minimum of  2 minutes prior.  This information is provided to the GM via the K bus.
•  Active crash signal from the MRS III control module.
• Lock  button  of  FZV  key  is  pressed  with  the  vehicle  is  already  locked  (interior  search
function).
The GM gradually reduces the full 12 volt power supply (linear reduction providing soft off)
until the lights are off when the following input signal statuses change:
•  Immediately after the ignition switch is turned to KL R with the driver's door hall sensor
door contact closed.
• When the vehicle is locked (single or double) with the door contacts closed. 
•  When  the  vehicle  door  contacts  are  closed.    The  lights  remain  on  for  20  seconds  and
then go to soft off.
•  After the interior search function is activated, the lights will automatically turn off (soft off)
after 8 seconds. 
•  After  16  minutes  with  a  door  contact  active  (open  door)  and  the  key  off,  the  lights  are
switched off (consumer cutoff function).
•  The component activation function of the DIS also has the ability to switch the lights. 
The Interior lighting output circuit of the GM is approximately 3.5 amps with all lights on. 
Page 51 of 64
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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  LED  in  the  rear  view  mirror  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,  tailgate
closed, etc.)  The inputs must be in a closed status for a minimum of 3 seconds 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 activation's.
• If  the  DWA  is  armed  a  second  time  within  10  seconds,  the  tilt  sensor  and  interior  pro-
tection sensor are also excluded as alarm activation components.  This function is use-
ful if the vehicle is transported on a train or flat bed truck to prevent false alarm activa-
tion's.
• While armed the tailgate can be opened with out the alarm being triggered as follows:
- If  opened  with  the  tailgate  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  tailgate  lock  cylinder  the  tailgate  key  position  switch
signals the GM and in the same manner prevents the alarm from activating.
In either case, when the tailgate is returned to the closed position, it is no longer con-
sidered as an activation signal. 
Panic Mode Operation: When the tailgate button is pressed and held, the GM is signaled
to activate the siren for the Panic Mode.  The panic mode will 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 III accepts it.  The EWS III signals the GM to unlock the doors and deactivate the
DWA.