mirror BMW 540I 1998 E39 Central Body Electronics ZKE Manual
Page 60 of 80
Mirror
Principle of Operation
The  output  stages  and  memory  storage  of  mirror  positions  is  handled  by  the  respective
door  modules.  The  positioning  of  the  mirrors  is  signaled  from  the  driver’s  door  switch
block/module. The signal passes over the P-Bus to the passenger’s door module. 
The  memory/recall  for  the  driver’s  mirror  comes  directly  into  the  door  module  from  the
memory switch. The operation for the passenger’s side mirror is carried out over the P-Bus
from the driver’s door module to the passenger’s door module. 
The memory positions are stored in each respective module. The memory position is rec-
ognized by the feedback potentiometers located on each mirror motor.
The reverse gear tilt feature for the passenger’s mirror is signaled from the GM, over the P-
bus, when reverse is selected and the mirror switch is set for the driver’s side.
Mirror heating is controlled by each respective door module. The GM receives the outside
temperature from the IKE and passes it to the door modules. The “ON” time for mirror heat-
ing is adjusted based on the outside temperature.
A pulsed heating cycle is used for the mirrors based on the outside temperature.
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Central Body Electronics ZKE III
Temperature<-10OC  -10 to 0OC 0 to 15OC 15 to 25OC >25OC
ON - duration  100% 75% 50% 25% 5%
E39 Shown 
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9. What type of sensor is used to detect the position of a seat with Memory?  What type
of signal does it produce?__________________________________________________
_________________________________________________________________________
10. How does the Seat Module communicate a request for a stored memory position with
the mirror modules?_______________________________________________________
________________________________________________________________________
11. On an E38 with Servotronic, why is the speed signal provided to the GM from both  
the IKE “A” signal and the K-Bus?___________________________________________
________________________________________________________________________
________________________________________________________________________
12. An E38 customer complains that when exiting the vehicle the steering wheel moves 
up. What is the cause of this?______________________________________________
________________________________________________________________________
13. How does the SZM monitor the Seat Heating temperature?_____________________
________________________________________________________________________
________________________________________________________________________
14. What circuits are controlled by Consumer Cut Off? ____________________________
________________________________________________________________________
________________________________________________________________________
15. If a technician double locked a 2000 MY E39 while still inside the vehicle, how could  
he/she exit the vehicle?____________________________________________________
________________________________________________________________________
________________________________________________________________________
16. How is the MY 2000 key charged?__________________________________________
________________________________________________________________________
________________________________________________________________________
17. How is the DWA Disarmed (emergency)?_____________________________________
________________________________________________________________________
18. What functions will deactivate the exterior door handle lighting? _________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________     
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Central Body Electronics ZKE III