Power Windows, Function - GF72.29-P-0001GN
MODEL 166 as of model year 2016
MODEL 292
Function requirements, general
- No overvoltage or undervoltage
- Circuit 15R ON or run-on active
Power-down: If circuit 15 is switched off, the power windows can still be operated for t = 5 minutes. If, during the run-on time, the circuits status or the door status is changed, the run-on time starts again.
The electronic ignition lock control unit transmits the circuit status of circuit 15 to the front door control units and rear door control units via the interior CAN.
Power windows, general
The side windows in the front and rear doors can be opened and closed with the power windows.
The convenience feature is a possibility to open and close the side windows from one central control point. The function is described in detail in the separate "Function description for theft protection and locking" in the partial function Convenience feature.
MODEL 166.8 as of model year 2016 with CODE 413 (Automatic panoramic sliding sunroof)
The pop-out windows between the C-pillar and D-pillar can also be opened and closed electrically. Detailed information concerning this can be found in the function "Electric pop-out window function".
Operation possibilities:
- Driver-side power window and outside mirror adjustment switch group:
- Left front power window switch
- Right front power window switch
- Left rear power window switch
- Right rear power window switch
- Passenger-side power window switch
- Left rear power window switch
- Right rear power window switch
Press and hold down the respective power window switch to perform a manual function. To start an automatic function it is sufficient to momentarily actuate beyond the catch point. Actuation takes places for as long (maximum t = 25 s) as the corresponding request is pending or until the side window reaches the lower or upper stop.
Control of the rear power window switch can be inhibited via the rear side window child safety lock switch.
The priority of possible functions depends on their requirement. A command with higher priority is performed if a function with lower priority is currently active. A lower priority function is interrupted first and is accomplished only after the second valid request. 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 request before the corresponding function can be activated.
Priority sequence:
- Driver-side power window and outside mirror adjustment switch group
- Remaining power window switches
- Actuation via diagnostic tester
- Close side windows via PRE-SAFE®
- Open side window with crash ventilation
- Comfort opening/closing via central locking
- Convenience opening/closing via recirculated air function
The power window functions comprise the following partial functions:
- Function sequence for normalization
- Function sequence for manual raising and lowering
- Function sequence for automatic raising and lowering
- Function sequence for actuation by PRE-SAFE®
- Function sequence for crash ventilation
- Function sequence for excess force limiter
- Function sequence for lockup reversing
- Function sequence for overheating protection
- Function sequence - child safety lock
Function sequence for normalization
Normalization is the basis for assigning the momentary positions to the positions sensed by the corresponding front door control unit and rear door control unit of the side window. For this purpose, it is necessary to manually close the corresponding side window completely and hold down the power window switch for approximately another t = 300 ms. If the power window switch is then released, the side window lowers approx. s =20 mm. The side window must then be closed completely within t= 4 s and the power window switch must be actuated for another t > 300_ms.
The corresponding signal path is described in the chapter "Manual raising and lowering".
The location counter in the relevant front door control unit or rear door control unit is set to z = 0 and normalization is completed. The location counter evaluates the signals from the Hall sensor integrated in the corresponding power window motor. The counter status is increased when opening and decreased when closing the side windows.
The ratio between counter status and armature rotations of the power window motor is 4 to 1.
The power windows are denormalized under the following conditions:
- Position counter status greater than maximum adjustment range
- Position counter status going beyond zero point tolerance for stored zero point
- No Hall sensor signals when power window motor in question is actuated
The reason for denormalization is stored in the corresponding front door control unit and rear door control unit. When the power windows are denormalized, only the manual raising and lowering functions are possible.
Normalization is a basic requirement to use the entire power window functions.
Additional function requirements for manual raising and lowering
- Child safety lock switched off (only for rear side window)
Function sequence for manual raising and lowering
Actuate and hold down the corresponding power window switch to the first catch point or beyond in the opening or closing direction. The actuation is accomplished as long as (max. t = 25 s) the corresponding request is present or until the lower or upper stop is reached.
Front side window in driver side:
The status of the left front power window switch in the power window switch group and driver side outside mirror adjustment are read in by the left front door control unit via the left door LIN. The left front door control unit then actuates the left front door power window motor and directly reads in the signals from the Hall sensor.
Front side window in passenger side:
The status of the right front power window switch in the power window switch group and driver side outside mirror adjustment is read in by the left front door control unit via the left door LIN and transmitted to the right front door control unit via the interior CAN. The right front door control unit then actuates the right front door power window motor and directly reads in the signals from the Hall sensor.
The status of the passenger side power window switch is read directly in by the right front door control unit. The right front door control unit then actuates the right front door power window motor and directly reads in the signals from the Hall sensor.
Rear side window:
The status of the rear power window switch in the power window switch group and driver side outside mirror adjustment is read in by the left front door control unit via the left door LIN and transmitted to the rear door control unit via the interior CAN. The corresponding rear door control unit then actuates the corresponding rear door power window motor and directly reads in the signals from the Hall sensor.
The status of the rear power window switch is read in directly by the corresponding rear door control unit. The corresponding rear door control unit then actuates the corresponding rear door power window motor and directly reads in the signals from the Hall sensor.
Additional function requirements for automatic raising and lowering
- Power windows normalized
- Child safety lock switched off (only for rear side window)
Function sequence for automatic raising and lowering
The corresponding power window switch must be actuated just beyond the first catch point in the "opening" or "closing" direction and then released.
The remaining function sequence corresponds to that of manual raising and lowering.
Actuation of the power window motors is discontinued automatically upon reaching the bottom or top stop. The automatic reserving function is active during automatic raising.
Additional function requirements for actuation by PRE-SAFE®
- Power windows normalized
Function sequence for actuation by PRE-SAFE®
When the Electronic Stability Program control unit recognizes an unstable driving status (e.g. understeering or oversteering), the side windows are closed to a defined position (s = 50 mm 4 mm before the upper limit stop) to minimize the risk of injuries).
The Electronic Stability Program control unit sends information about the PRE-SAFE® status and the request for PRE-SAFE® adjustment via chassis CAN 1, the electronic ignition lock control unit and the interior CAN to the front door and the rear door control units. The corresponding front door control unit then actuates directly the front door power window motor. The corresponding front door control unit then actuates directly the rear door power window motor.
Actuation by PRE-SAFE® is interrupted in case of:
- Active automatic reversing function (side windows reversed)
- Blockage detection
- Request from corresponding power window switch
Additional function requirements for crash ventilation
- Power windows normalized
Function sequence for crash ventilation
Smoke particles are produced in the vehicle interior when the pyrotechnical restraint equipment is triggered. To ensure that the smoke particulates are quickly removed, the front side windows are automatically opened after an accident to a defined position (s = 50 mm 4 mm before the upper limit stop).
The supplemental restraint system control unit sends the crash signal via the chassis CAN 1, electronic ignition lock control unit and interior CAN to the front door control units. The front door control units then actuate the front door power window motors directly.
The crash ventilation is interrupted:
- Blockage detection
- Request from corresponding power window switch
Crash ventilation is blocked for the following:
- Active PRE-SAFE® function
Additional function requirements for excess force limiter
- Window position in area of s = 3 to 230 mm (opening width)
- Power windows normalized
Function sequence for excess force limiter
The excess force limiter function operates when the window is raised automatically or manually, however, at different sensitivity levels (escalation stages). The power consumption of the power window motor serves as a reference for excessive force.
The system is designed adaptively to prevent mechanical sluggishness being evaluated as pinching. This means that the system recognizes sluggishness by the increased current consumption of the specific power window motor and calculates an additional force of F = 10 N for the next request. This ensures a constant speed when opening or closing the power windows even in the face of advanced wear or external influences such as moisture and ice.
The adaptation is limited to a maximum value of F = 80 N. The individual escalation stages depend on the operating request and history and are shown in the table below.
| Manual closing | 1. Actuation (escalation stage 1) | 2nd actuation (escalation stage 2) | 3rd actuation (escalation stage 3) |
|---|---|---|---|
| Holding power window switches | Stops at F = 100 N + 15 N | Stops at F = 130 N + 15 N | Actuation remains active |
| Releasing power window switches | Reversing by s = 20 mm + 5 mm | Reversing by s = 20 mm + 5 mm | Actuation stopped |
| Automatic closing | |||
| Releasing power window switches | Stop at F = 60 N - 10 N; reversing s = 125 mm + 5 mm | Stop at F = 80 N - 10 N; reversing by s = 125 mm + 5 mm | Only manual raising possible |
If the power window switch is actuated again within t 2 after completion of the reversing maneuver, the status changes. When the power window switch is actuated again after a time of t = 2 s, escalation stage 1 (1st actuation) is started.
If pinching is recognized during automatic raising triggered by the comfort closing function via the air recirculation function, the corresponding front door control unit or rear door control unit starts with escalation stage 1 (1st actuation).
If pinching is recognized during automatic raising, actuated by the KEYLESS-GO function (with CODE 889 (Keyless-Go)) or the closing side window function by PRE-SAFE®, the corresponding front door control unit or rear door control unit starts with escalation stage 2 (2nd actuation).
When the power windows are not normalized, the excessive force limiter is activated starting at a pinching force of F = 100 N. The side window always reverses when it runs into the upper seal.
On power windows which have not been normalized, the excess force limiter is deactivated within a short time after two closing requests.
This allows normalization at the upper stop.
Mechanical vibrations caused by bad road conditions are not recognized as pinching and do not lead to reversal of the corresponding power window. The "bad road recognition" required for this purpose is activated starting at a speed of > 8 km/h.
Additional function requirements for lock-up reversing
- Power windows normalized
Function sequence for lockup reversing
If the front door control unit or rear door control unit in question recognizes a change in the Hall sensor signals within t = 150 + 20 ms or an increase in the force of F = 160 N while the side window is rolling up, this is evaluated as pinching. Raising is immediately stopped and the window opens s = 20 mm. The lock-up reversing function depends on the type of rolling up.
Escalation stages for excess force limiter function apply.
Function sequence for overheating protection
The protection of the power window motors is guaranteed by a thermal protection software in the corresponding front door control unit or rear door control unit. The software simulates temperature characteristics depending on the operating time. The parameters required for this were determined in tests and are stored in the associated front door control unit or rear door control unit.
The permissible ambient temperature range of the power window motors is: T = -40 °C to +85 °C.
Function sequence - child safety lock
When the child safety lock is switched on, the rear side windows cannot be opened and closed by actuating the rear power window switch.
Actuations already activated are interrupted immediately by the rear door power window motors. The child safety lock can be switched on and off via the rear side window child safety switch in the power window switch group and driver side outside mirror adjustment.
The status of the rear side window child safety lock is read by the left front door control unit via the front door LIN. The left front door control unit transmits the status of the child safety lock to the rear door control unit via the interior CAN. The rear side window child safety lock switch signals the driver that the child safety lock is activated via an integrated LED. To this end, the left front door control unit sends a request to actuate the LED via the left front door LIN to the power windows switch group and the driver side outside mirror adjustment.
If the position of the rear side window child safety lock switch can no longer be read with certainty, the child safety lock function is regarded as permanently switched on.
| Electrical function diagram for power windows | PE72.29-P-2050-97NBA | ||
| Overview of system components for power windows | GF72.29-P-9993GN |