Code BMW 740IL 2000 E38 Central Body Electronics ZKE Manual

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