Windshield Wiper, Function - GF82.30-P-3004RF
Model 205, Model 253
Function requirements, general
- Circuit 15R ON
The electronic ignition lock control unit (N73) sends the status of circuit 15 via interior CAN (CAN B) to the front SAM control unit (N10/6).
Wiping windshield, general
The windshield wiper function is comprised of the following subfunctions:
- Intermittent wipe function sequence
- Single wipe function sequence
- Function sequence of wiping at specified speed
- Function sequence for interrupting wiping during engine start
- Wiper start suppression function sequence
- Function sequence for wipe stop
- Function sequence for automatic speed reduction of windshield wiper system (except CODE 494 (USA version))
Intermittent wipe function sequence
The intermittent wipe function is activated by turning the combination switch (S4) to switch position "1" (rain sensor (B38/2b1) in the rain/light sensor with additional functions (B38/2) low sensitivity), or to switch position "2" (rain sensor high sensitivity).
When the system is switched from switch position "0" to switch position "1" or "2", there is an automatic wipe cycle, the so-called "Reaction wipe".
The steering column tube module control unit (N80) directly reads in the switch position of the combination switch and sends it to the front SAM control unit via the chassis FlexRay (Flex E), electronic ignition lock control unit and interior CAN.
The front SAM control unit sends the requested sensitivity via the rain/light sensor LIN (LIN B16) to the rain/light sensor with additional functions.
The rain/light sensor with additional functions uses the requested sensitivity and the amount of windshield wetness as a basis for calculating the frequency of required wipe procedures and then sends the corresponding wipe request via the rain/light sensor LIN to the front SAM control unit. The front SAM control unit then actuates the wiper motor (M6/1) over the rain/light sensor LIN correspondingly.
The wetness of the windshield is detected by the rain sensor in the rain/light sensor with additional functions. The rain/light sensor with additional functions reads in the signals from the rain sensor directly and evaluates them.
The intermittent wipe function is interrupted under the following conditions:
- Activating wipe/stop function
- Activating wash function
- Activating single wipe function
- Activation of afterwipe function
- Activating wiper startup suppression function
- Turning combination switch to switch position "0", "3" or "4"
- Blocking of wiper motor
- Missing or faulty rain sensor data
Additional function requirements for single wipe
- Combination switch in switch position "0", "1" or "2"
The steering column tube module control unit reads in the switch position of the combination switch directly and sends it via chassis FlexRay, the electronic ignition lock control unit and interior CAN to the front SAM control unit.
Single wipe function sequence
The single wipe function is activated by briefly pressing the multifunction switch up to the catch point. If the combination switch is pressed for a longer period, wiping takes place in accordance with the duration for which it is pressed, but for a maximum of t = 30 s only.
The front SAM control unit actuates the wiper motor over the rain/light sensor LIN accordingly. If the windshield wiper is not located in the rest position, the request of the combination switch is ignored.
If the combination switch is pressed in the "0" switch position and held down for longer than t = 30 s, the SAM control unit evaluates this as a "stuck combination switch" and aborts the single wipe function, despite the pending request.
The speed at which the windshield wipers are moved corresponds to the wiping speed in switch position "3" (continuous wipe at low speed).
The single wipe function is interrupted under the following conditions:
- Activating wash function
- Activation of afterwipe function
- Activating wipe interruption during engine start function
- Blocking of wiper motor
Function sequence of wiping at specified speed
The wipe function with predefined speed is activated by turning the combination switch to switch position "3" (continuous wipe at slow speed), or switch position "4" (continuous wipe at fast speed). The steering column tube module control unit reads in the switch position of the combination switch directly and sends it via chassis FlexRay, the electronic ignition lock control unit and interior CAN to the front SAM control unit. The front SAM control unit then actuates the wiper motor over the rain/light sensor LIN correspondingly.
The wash function with predefined speed is interrupted under the following conditions:
- Activating wipe/stop function
- Activating wash function
- Activation of afterwipe function
- Activation of speed reduction function (except CODE 494 (USA version))
- Turning combination switch to switch position "0", "1" or "2"
- Blocking of wiper motor
Function sequence for interrupting wiping during engine start
During engine start, the front SAM control inhibits the actuation of the wiper motor. Any wiping procedure already started is terminated. The engine start is recognized by the transmission of the status of circuit 50. The electronic ignition lock control unit transmits the status of circuit 50 to the front SAM control unit via the interior CAN.
Additional function requirements for wiper start suppression
- Vehicle speed v < 3 km/h
- Combination switch in switch position "1" or "2"
- Rain sensor has detected a wet windshield
The instrument cluster (A1) information on the vehicle speed over the user interface CAN (CAN HMI), electronic ignition lock control unit and interior CAN to the front SAM control unit.
The steering column tube module control unit reads in the switch position of the combination switch directly and sends it via chassis FlexRay, the electronic ignition lock control unit and interior CAN to the front SAM control unit.
The wetness of the windshield is detected by the rain sensor in the rain/light sensor with additional functions. The rain/light sensor with additional functions reads in the signals of the rain sensor directly and sends the corresponding wipe request over the rain/light sensor LIN (LIN) to the front SAM control unit.
Wiper start suppression function sequence
The wiper startup suppression is intended to prevent people from being sprayed with water from the windshield when getting in or out of the vehicle as the result of an initiated wipe operation. The windshield wipers remain in the park position despite a wipe request triggered manually or automatically.
If a front door is opened during wiping, the front SAM control unit interrupts the actuation of the wiper motor.
The opening of the left front door is recorded through the status of the left front door rotary tumbler switch (A85s1) in the left front door lock (A85). The left front door control unit (N69/1) reads in the status of the left front door rotary tumbler switch directly and sends it to the front SAM control unit via interior CAN.
The opening of the right front door is recorded through the status of the right front door rotary tumbler switch (A85/1s1) in the right front door lock (A85/1). The right front door control unit (N69/2) reads in the status of the right front door rotary tumbler switch directly and sends this via interior CAN to the front SAM control unit.
The front SAM control unit reads in all relevant information, evaluates it and interrupts actuation of the wiper motor. An already started wiping procedure is not interrupted immediately. The wipers continue to move to the park position.
The wiper start suppression is deactivated under the following circumstances:
- Vehicle speed: v ≥ 3 km/h
- Combination switch in switch position "3" or "4"
- Single wipe or wash function activated
- Driver and front passenger door closed and drive range "D" or "R" engaged (transmission 722, 724, 725, model 253.99)
- Clutch operated (transmission 716)
- Change from circuit 15C to circuit 15R
Model 205 with transmission 722
Model 205, Model 253 with transmission 724, 725
With circuit15R On, no information on the current gear range is sent to the front SAM control unit by the fully integrated transmission control unit (Y3/8n4) over the drive train CAN (CAN C1), powertrain control unit (N127), chassis FlexRay, electronic ignition lock control unit and interior CAN. Instead, "Gear range N" is constantly sent. The current gear range is only available as of circuit 15 On. The wiper startup suppression function is not canceled by circuit15R On through the status of the gear range. The electronic ignition lock control unit sends the status of circuit 15 to the front SAM control unit via the interior CAN.
Model 205, Model 253 with transmission 716
The actuation of the clutch is sensed by the clutch pedal switch (S40/3). The CDI control unit (N3/9) (diesel engine), or the ME-SFI [ME] control unit (N3/10) (gasoline engine) reads in the status of the clutch pedal switch directly and sends it via drive train CAN, powertrain control unit, chassis FlexRay, electronic ignition lock control unit and interior CAN to the front SAM control unit.
Additional function requirements for wipe stop
- Wipe or wash function activated
- Vehicle speed v < 3 km/h
The steering column tube module control unit reads in the switch position of the combination switch directly and sends it via chassis FlexRay, the electronic ignition lock control unit and interior CAN to the front SAM control unit.
The instrument cluster sends the vehicle speed to the front SAM control unit over the user interface CAN (CAN HMI), electronic ignition lock control unit and interior CAN.
Function sequence for wipe stop
The wipe stop function prevents the wiper motor from being actuated by the front SAM control unit when the engine hood is open and thus causing damage to the vehicle. If the engine hood is opened while driving (v < 3 km/h), the front SAM control unit immediately stops the wiper motor actuation.
At a speed of v > 6 km/h, the wiper stop function is deactivated, i.e. the wiper motor is actuated again from this speed onwards.
The open engine hood is detected by the status of the right engine hood contact switch (S62/42), and the left engine hood contact switch (S62/43). The front SAM control unit directly reads in the status of the right engine hood contact switch and the left engine hood contact switch.
Additional function requirement for automatic speed reduction of windshield wiper system (except CODE 494 (USA version))
- Combination switch in switch position "3" or "4"
The instrument cluster sends the vehicle speed to the front SAM control unit over the user interface CAN (CAN HMI), electronic ignition lock control unit and interior CAN. The steering column tube module control unit reads in the switch position of the combination switch directly and sends it via chassis FlexRay, the electronic ignition lock control unit and interior CAN to the front SAM control unit.
Function sequence for automatic speed reduction of windshield wiper system (except CODE 494 (USA version))
It is assumed that the windshield does not become as wet at slow speeds. For this reason, the front SAM control unit reduces the wiper speed as soon as vehicle deceleration from v > 6 km/h to v < 3 km/h is detected.
The automatic speed reduction function of the windshield wiper system is interrupted under the following conditions:
- Vehicle speed v > 6 km/h
- Changing wiper speed
- Activating single wipe function
- Activating wash function
| Electrical function schematic for windshield wiper | PE82.30-P-2051-97FBA | ||
| Overview of system components for windshield wiper system | GF82.30-P-9996RF |