Page 11 of 80

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.
11
Central Body Electronics ZKE III
12510111.eps 
     
        
        Page 54 of 80

Rear  Seat  Interior/Reading  Light  Units: In
each C pillar trim panel is an interior/reading light
unit. 
These  units  each  contain  an  interior  light  that  is
controlled  with  the  front  interior  light  and  a
mechanically  switched  reading  light  on  the  con-
sumer 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. 
On E38 and E53 the doors also contain courtesy
lights at the lower edge of the door panel (1).
Door  Warning  Lights  (E38): The  additional
“red”  warning  lights  are  installed  in  the  edge  of
the  doors  (2).  These  lights  are  illuminated  when
the doors are opened.
Illuminated  Transmission  Shift  Indicator
(E38): The  E38  uses  a  microprocessor  for  dis-
playing the shifter position in the center console.
The  processor  receives  shift  position  signals
from  a  console  mounted  range  switch.  The
processor  illuminates  the  LED corresponding  to
the position of the range selector.
The  park  position  LED  will  remain  “on”  after  the
ignition  is  switched  off  and  stay  on  until  the  GM
goes into the “sleep” mode. 
Soft Lighting Feature: The GM provides progressive voltage (up to 12v) providing the soft
on feature
to the interior lighting circuit when the interior lights are required. The GM grad-
ually reduces the full 12 volt power supply providing soft off 
when interior light deactivation
is required. 
54
Central Body Electronics ZKE III
Park
Position
LED 
     
        
        Page 59 of 80

59
Central Body Electronics ZKE III
System Components
- with Principle of Operation
Manual Operation:The manual adjustments of the seat, mirrors and steering column are
carried out with the respective switches as with the previous systems.
The  mirror  adjustment  switch  is  located  in  the  driver’s  switch  block.  The  mirror  operation
input is a digital signal that is processed by each respective module for mirror positioning.
Memory Storage: The parameters for storing memory positions are are as follows:
• With  the  transmission  range
selector  in  “P”  and  the  mirror
change over switched to the left,
switch  the  ignition  on  and  press
the “M” on the memory switch.
• The memory indicator lamp swi- 
tches on for 7 seconds.
• Press one of the three position 
switches (1, 2 or 3) within the 7  
second memory period.
• The current positions of the mir-
rors, seat and steering column 
are stored for recall.
The positions of the mirrors are stored in the respective door
modules based on the position of the feedback potentiome-
ters. The positions of the seat and steering column are stored
in the seat module, based on the ripple count.
Recalling a memory position setting is possible by either
pressing and holding the recall switch (1, 2 or 3) with KL 15
“ON” or tapping the recall button (1, 2 or 3) with:
• The driver’s door open and KL 15 “OFF”.
• KL R ON and KL 15 “OFF”. 
The recall movement can be interrupted at any time by touching any of the adjusting
switches.
E38/E39
E53 
615200133.tiff 
     
        
        Page 75 of 80

General Functions of ZKE III
Consumer Cut Off
The Consumer Cut Off function interrupts battery voltage to circuits preventing inadvertent
battery  drain  if  one  of  these  consumers  were  to  remain  activated.  Circuits  controlled  by
consumer cut off will be switched off as the GM enters into the sleep mode.
For example, the interior lights are connected to the consumer cut out circuit (KL 30) and
can  remain  on  if  one  of  the  control  switches  are  left  on.  The  consumer  cut  off  will  deacti-
vate KL 30 to the interior lighting after 16 minutes (or with the DISplus/MoDIC).
The  following  circuits  are  con-
trolled by consumer cut off:
• Map/Reading Lights
• Glove Box/Luggage Compart- 
ment Lights
• Transmission Range Indicator  
Light
• Overload Protection Relay for
- Power Seat Motors
- Steering Column Motors
Overload Protection
The seat and steering column motors receive
operating  power  through  the  consumer  cutoff/
overload protection relay module. The consumer
cutoff  signal  from  the  GM  signals  the  relay  to
maintain operating power to the consumers. 
If the relay module detects an increase in amper-
age (overload) the relay will open. The relay mod-
ule  (K-72)  is  located  in  the  electrical  carrier
behind  the  glove  box.  The  relay  is  reset  by
switching  the  ignition  “off”  for  16  minutes,  dis-
connecting the relay or the DISplus/ MoDIC. 
75
Central Body Electronics ZKE III
E38 Shown
Overload
Protection Relay
Module