Power Windows (PW (EFH)), Function - GF72.29-P-0003FG

Model 213 up to model year 2021 

Courtesy of MERCEDES-BENZ USA

Shown on model 213 

Function requirements, general 

• No overvoltage or undervoltage
• Circuit 15R r circuit 15 ON o run-on time active

Run-on:

If terminal 15R is switched off, the power windows can still be operated for 5 min. 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.

The Front door control units sense the status of the Front doors (open or closed).

Power windows, general 

The side windows of the vehicle can be opened and closed electrically.

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 (except Code 297 (Roller sun blinds in Rear doors))
• Right Rear power window switch (except Code 297 (Roller sun blinds in Rear doors))
• Left Rear door switch group (with Code 297 (Roller sun blinds in Rear doors)):
  • Left Rear side window roller sun blind and power window switch
  • Right Rear side window roller sun blind and power window switch
• Right Rear door switch group (with Code 297 (Roller sun blinds in Rear doors)):
  • Right Rear side window roller sun blind and power window switch
  • Left Rear side window roller sun blind and power window switch

Press and hold down 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 place for as long (maximum 25 s) as the corresponding request is pending or until the side window reaches the lower or upper stop.

Operation via controls in the Rear 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:

1. Driver-side power window and outside mirror adjustment switch group
2. Remaining power window switches
3. Actuation via diagnostic tester
4. Close side windows via PRE-SAFE®
5. Open side window with crash ventilation
6. Comfort opening/closing via central locking
7. 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. To this end, the relevant side window must be fully closed manually, and the power window switch must continue to be pressed for approx. 300 ms. When the power window switch is then released, the side window lowers approx. 20 mm. The side window must now be closed fully once more within 4 s and the power window switch held for another 300 ms.

The corresponding signal path is described in the chapter "Manual run-up/run-down".

The location counter in the relevant Front door control unit or Rear door control unit is set to 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: 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 (for Rear side window control points

  Function sequence for manual raising and lowering 

  Actuate and hold down corresponding power window switch until the first catch point in the "Opening" or "Closing" direction. Actuation lasts as long (maximum 25 s) as the corresponding request is pending or until the lower or upper stop is reached.

  The glass pane of the side window reduces the movement speed during run into the upper seal. From 01.06.2018, the movement speed will not be reduced at a vehicle speed > 120 km/h.

  Front driver side window 

  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 passenger side window 

• 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.
• 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.

  Rear side window (except Code 297 (Roller sun blinds in Rear doors)) 

• 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.
• 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.

  Left Rear side window (with Code 297 (Roller sun blinds in Rear doors)) 

• The status of the power window switch and left Rear side window roller sun blind in the left Rear door switch group is read in by the left Rear door control unit via the left Rear door LIN. The left Rear door control unit then actuates the left Rear door power window motor and directly reads in the signals from the Hall sensor.
• The status of the power window switch and left Rear side window roller sun blind in the right Rear door switch group is read in by the right Rear door control unit via right Rear door LIN and transmitted to the left Rear door control unit via the interior CAN. The left Rear door control unit then actuates the left Rear door power window motor and directly reads in the signals from the Hall sensor.
• The status of the left 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 Front door LIN and transmitted to the left Rear door control unit via interior CAN. The left Rear door control unit then actuates the left Rear door power window motor and directly reads in the signals from the Hall sensor.

  Right Rear side window (with Code 297 (Roller sun blinds in Rear doors)) 

• The status of the power window switch and right Rear side window roller sun blind in the right Rear door switch group is read in by the right Rear door control unit via right Rear door LIN. The right Rear door control unit then actuates the right Rear door roller sun blind motor and directly reads in the signals from the Hall sensor.
• The status of the power window switch and right Rear side window roller sun blind in the left Rear door switch group is read in by the left Rear door control unit via left Rear door LIN and transmitted to the right Rear door control unit via interior CAN. The right Rear door control unit then actuates the right Rear door roller sun blind motor and directly reads in the signals from the Hall sensor.
• The status of the right 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 Front door LIN and transmitted to the right Rear door control unit via interior CAN. The right Rear door control unit then actuates the right Rear door roller sun blind 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 (for Rear side window control points

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
• Side windows opened further than PRE-SAFE® position

Function sequence for actuation by PRE-SAFE® 

If the Electronic Stability Program detects an unstable vehicle status (e.g. understeer or oversteer), the side windows are closed to a defined position (50 mm + 4 mm before upper stop) to minimize the risk of injury.

The electronic stability program transmits the information for the PRESAFE® status and the request for PRE-SAFE® adjustment via chassis FlexRay, electronic ignition lock control unit and interior CAN to the Front door control units and 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
• Blockage detection
• Request via corresponding power window switch

Additional function requirements for crash ventilation 

• Front power windows normalized
• Front side windows closed more than 50 ± 4 mm before upper stop

Function sequence for crash ventilation 

Smoke particles are produced in the vehicle interior when the pyrotechnical restraint equipment is triggered. To ensure that these smoke particles are removed quickly, the Front side windows are automatically opened to a defined position (50 ± 4 mm before upper stop) in event of an accident.

The supplemental restraint system control unit sends the crash signal over the user interface CAN, 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 via corresponding power window switch

The crash ventilation is inhibited when the PRE-SAFE® function is activated.

Additional function requirements for excess force limiter 

• Window position in the range from 3 to 230 mm (clear opening)
• 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 power consumption of the respective power window motor, and calculates an additional force of 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	Stop at 100 N (+15 N)	Stop at 130 N (+15 N)	Actuation remains active
Releasing power window switches	Reverse 20 mm (+5 mm)	Reverse 20 mm (+5 mm)	Actuation stopped
Automatic closing
Releasing power window switches	Stop at 60 N (-10 N); Reverse 125 mm (+5 mm)	Stop at 80 N (-10 N); Reverse 125 mm (+5 mm)	Only manual raising possible

If the power window switch is actuated again within 2 s after reversing is finished, the status changes. If the power window switch is actuated again after a time of 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).

If power windows are not normalized, the excessive force limiter is active starting at a pinching force of 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 therefore 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 respective Front door control unit or Rear door control unit does not recognize within 150 ms + 20 ms a change in the Hall sensor signals or an increase in force of 160 N from the set distance already traveled while the side window is closing, this is evaluated as blocking. Closing is stopped immediately and the side window is opened 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: -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 or closed via the Rear power window switch group (except Code 297 (Roller sun blinds in Rear doors)) or via the Rear door switch groups (with Code 297 (Roller sun blinds in Rear doors)). Actuations already activated are interrupted immediately by the Rear 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. For this purpose, the left Front door control unit transmits the request to actuate the LED to the Rear side window child safety switch via the left Front door LIN.

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.

	Function schematic for power windows		PE72.29-P-2050-97DBA
	Overview of system components for windows and sightproofing		GF67.00-P-9999FG