GF72.29-P-0003RC Power Windows (PW (EFH)), Function
GF72.29-P-0003RC Power Windows (PW [EFH]), Function
- refinement package
- as of model year 09
Function requirements, general
^ Circuit 15R ON or circuit 15 ON
^ No overvoltage or undervoltage
^ Run-on time active (up to t = 5 min. after c. 15R OFF, with front doors not yet opened and vehicle not locked from outside)
The circuit status is transmitted by the EIS control unit (N73) to the interior CAN.
The door status is sensed by the left door contact switch (S17/3) and right door contact switch (S17/4), read in by the rear SAM control unit with fuse and relay module (N10/2) and transmitted to the interior CAN..
Power windows (PW), general
The front side windows can be opened and closed with the power window lifters.
The rear side windows can only be operated in combination with the Vario roof. For this purpose see separate Vario roof function description.
The convenience feature is a possibility to open and close the side windows from one central control point. For this purpose see separate convenience feature function description.
Operation possibilities:
- Driver-side power window switch group (S20/1)
- Left power window switch (S20/1s1)
- Right power window switch (S20/1s2)
- Front passenger power window switch (S21/2)
Only the passenger side window can be opened and closed with the passenger power window switch.
The power window system comprises the following partial functions:
^ Function sequence for raising and lowering
^ Function sequence for position recognition
^ Function sequence for normalization
^ Function sequence for denormalization
^ Function sequence for excess force limiter
^ Function sequence for anti-pinch protection
^ Function for short stroke opening/closing
^ Function sequence for thermal protection
^ Priority function sequence
Additional function requirements for raising and lowering
^ Power window normalized (only for automatic raising)
Function sequence for raising and lowering
Press and hold down corresponding power window switch to perform a manual function.
To start an automatic function it is sufficient to momentarily actuate beyond the catch point.
Driver-side control point:
The driver-side power window switch group is read in directly by the left door control unit. When the left power window switch is actuated, the left door control unit (N69/1) actuates the left front power window motor (M10/3).
When the right power window switch is actuated, the left door control unit transmits the request to the right door control unit (N69/2), which actuates the right front power window motor (M10/4).
Front passenger control point:
The position of the passenger-side power window switch is read directly by the right front door control unit. When actuated, the right door control unit actuates the right front power window motor.
The actuation is accomplished as long as the corresponding request is present or until the lower or upper stop is reached, however, max. t = 25 s.
Function sequence for position recognition
The location counter in the door control unit in question evaluates the signals from the Hall sensor on the power window motors. Depending on the actuation direction, the counter is increased when "opening", decreased when "closing" the window The zero position is the upper stop (side window fully closed) and is set by the normalization procedure.
Normalization function sequence
Normalization means learning in the upper mechanical window stop (zero point) into the door control unit.
It is required for the automatic raising function and the short stroke function.
For this purpose completely close corresponding side window with the manual raising function. Continue to hold down corresponding switch for approx. t = 0.3 s.
The location counter in the responsible door control unit is then set to z = 0.
Function sequence for denormalization
The power windows are denormalized under the following circumstances:
- The door control unit recognizes a location counter status greater than the maximum window travel.
- The door control unit recognizes a location counter status beyond the tolerance of the zero point stored
- The door control unit recognizes erroneous or absent Hall sensor signals during actuation.
- If on-board power supply voltage is not present for t > 60 s
Additional function requirements for excess force limiter
^ Front side window open (s = 4 mm to 230 mm)
^ Front side window closed automatically
^ Power windows normalized
Function sequence for excess force limiter
The door control units can recognize an increase in force when closing the side window (e.g. pinching) by monitoring the power consumption of the front power window motors. In this case the closing procedure is terminated immediately and the side window is opened approx. s = 70 mm.
If a side window is raised again on the driver-side within t = 10 s, this is performed without excess force limiter.
Additional function requirements for anti-pinch protection
^ Power windows normalized
^ Side window open (s = 4 mm to s = 230 mm)
^ Front side window closed
Function sequence for anti-pinch protection
If, during automatic raising of the window, the left/right door control unit does not recognize a change of the Hall sensor signals, this is evaluated as pinching.
Raising is immediately stopped and the side is opens s = 70 mm.
Additional function requirements short stroke opening/closing
^ Power windows normalized
^ Window position s < 4 mm inside width
Function for short stroke opening/closing
When the driver or passenger door is opened, the associated side window is lowered to the short stroke position.
As long as the short stroke is activated, the corresponding side window cannot be closed manually.
After the last door is closed, the corresponding side windows are closed to the end position.
The short stroke position is at s = 4 mm to 1 mm inside width, measured between the bottom edge of the outer sealing lip and the top edge of the window.
Function sequence for thermal protection
The overheating protection for the power window motors is guaranteed by a software thermal protection in the corresponding door control unit. After a waiting time of t = 5 s to t = 10 s the power window motor can be switched on again.
In addition, the power window motors are protected against overheating by a thermal protection switch.
Priority function sequence
1. Driver power window switch group
2. Front passenger power window switch
3. Convenience opening/closing via transmitter key (A8/1)
4. Convenience opening/closing via recirculated air function
A command with higher priority is performed if a power window function with lower priority is currently active.
The function with lower priority is interrupted first and with the second valid actuation the corresponding function starts. If a command with lower priority is still present after completion of an operation request with higher priority, the former command is ignored.
It is first necessary for the controls to recognize non-actuation of the lower priority command before the corresponding function can be activated.
A command with lower priority cannot affect an active power window function of higher priority.
