2000 BMW 740IL Code

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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Central Body Electronics ZKE III
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Power Window Motors: The window motors are mounted on the cable regulators. The
window motor control circuit consists of two wires for operating the motor in both direc-
tions.
The motors are activated by relays in the GM of door
modules (front doors). The relays provide either power
or ground depending on the direction of window travel.
The GM controls the polarity of the motor based on a
request to run the window (window switch,
Convenience Opening/ Closing).
The windows are run to the limit stops which is detect-
ed by an amperage increase in the control circuit.
Additionally, the window run cycle is limited to a 6-8
second duration if in case the amperage increase is not
detected or there is a malfunction with the regulator.
Window Motor Limit Stop Function: If the windows are run up and down continuously
a limit stop function is activated to prevent the window motors from overheating. The GM
monitors the number of times the window motors are activated. Each cycle is counted and
stored in memory.
If the repetitive window activation (up/down) exceeds one minute, the GM deactivates the
internal relays and disregards any further input requests. The GM provides motor activation
after a short duration but not for the full one minute monitoring cycle. Over time, the GM
slowly reverses the stored count of activation until the stored number equals 0.
Convenience Opening/Closing: The GM provides the convenience open/close feature
providing control of the power windows (and sunroof) from outside the vehicle with the key
in the driver’s door lock cylinder. The FZV provides the same function for the opening only.
• The anti-trap feature is active during convenience closing from the driver’s door lock.
• The convenience open feature provides outside activation of the windows and sunroof
in the same manner.
• If the GM receives a request to operate convenience close or open for more than 110
seconds, the function is deactivated and a fault code is stored.
• The Car Memory Feature can activate and deactivate the Convenience Open Feature
from the FZV’s control.
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Central Body Electronics ZKE III
FRONT DOOR
REGULATOR
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Sunroof
Purpose of the System
When the ignition key is in accessory or “on”
position press the switch or slide it to the desired
direction to lift (2), open (1) or close the sunroof.
When lifting, the headliner retracts several inch-
es. The sunroof can continue to operate after
the ignition has been switched off as long as one
of the front doors has not been opened.
Mechanically, the sunroofs are similar in design.
Some vehicles are equipped with the steel roof
while others are equipped with the glass (moon)
roof.
The anti-trap feature of the sunroof uses a hall
sensor to detect obstructions while the sunroof
is closing. The initialization procedure must be
carried out to allow the sunroof to operate in the
opening direction and allow the anti-trap feature
to function.
The anti-trap is shut down 4mm
prior to full closed and during the tilt closing
function.
System Components
Sunroof Switch:Mounted in the sunroof motor trim cover, the switch provides coded
ground signals for system operation. The following signals are generated over three wires:
• Rest position.
• Slide open request (press and hold switch - first detent of
open position).
• Automatic slide open request (press further to second
detent and release).
• Tilt open (press and hold).
• Slide close request (press and hold switch - first detent of
close direction).
• Automatic slide close request (press further to second
detent and release).
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Central Body Electronics ZKE III

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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Central Body Electronics ZKE III