Wiper and Washer System
Wiper And Washer System
The wash / wipe functions may be operated from terminal 30B ON.
The windscreen wipers are driven by an electric motor with a reduction gear.
The windscreen wipers are activated by the wiper module. The wiper module is connected to the junction box electronics (JBE) via LIN bus.
The rear window wiper is activated directly by the junction box electronics (JBE), as are the washer-nozzle heating.
The rain/driving light sensor is fitted as series standard. This generally enables an automatic mode for the windscreen wipers.
The headlight-cleaning system is offered as an optional extra. The headlight-cleaning system is mandatory with the "bi-xenon for low-beam / high-beam headlights" in countries with approval for Europe.
The Touring has a rear window wiper as series standard with a separate rear window washer pump.
Brief description of components
The following components supply an input signal for the wipe / wash function:
Wiper switch
The wiper switch is operated with one touch. The wiper switch does not lock into place. The signal from the wiper switch is forwarded by the steering column switch cluster (SZL) to the central gateway module (ZGM). The ZGM control module sends the signal to the junction box electronics (JBE).
The axial button on the wiper switch activates the automatic mode (automatic control via the rain/driving light sensor). If the automatic mode is disabled, intermittent operation is controlled on a speed-dependent basis.
Rain / driving light sensor
The rain/driving light sensor is located on the windscreen in the mirror base. The rain/driving light sensor consists of a driving light sensor and a rain sensor. It picks up the rain intensity for wiper control and surrounding brightness for control of the low-beam headlights.
The rain/light sensor is connected to the junction box electronics (JBE) via a LIN bus.
Wiper module
The windscreen wipers are operated by the wiper module.
The wiper module is controlled by the junction box electronics.
The wiper module is connected to the junction box electronics via LIN bus.
The following control modules are involved in wash/wipe system functions:
JBE: Junction Box Electronics
The junction box electronics (JBE) activate the wiper / wash system (also the wiper / wash system for the rear window on the Touring).
The junction box electronics (JBE) are connected via the K CAN e.g. with:
- Central gateway module (ZGM)
The junction box electronics (JBE) are connected via the LIN bus e.g. with:
- Wiper module
- Rain / driving light sensor
SZL: Steering column switch center
The steering column switch cluster (SZL) forms the interface between the wiper switch and the central gateway module (ZGM).
ZGM: Central gateway module
The central gateway module (ZGM) forms the gateway between the K CAN and the wiper switch.
The following actuators are activated for the wipe / wash function:
Wiper drive unit
The wiper system is a two-arm synchronized system with stroke control (jointed in four places).
The wiper drive is a rotary motor without an electronic module. The wiper motor is located in the wiper module. The wiper module is activated by the junction box electronics (JBE) via a double relay.
The end position (rest position) of the wiper drive is detected by a reset contact integrated in the wiper drive.
Touring:
The rear window wiper drive is mounted on the rear window.
The rear window wiper drive is activated by the junction box electronics (JBE) via a relay.
The end position (rest position) of the rear window wiper drive is detected by a reset contact integrated in the wiper drive.
Washer pump for windscreen and rear window (Touring)
Both wash pumps are attached to the washer fluid container. The wash pumps are actuated by the junction box electronics (JBE). The washer nozzle cannot be adjusted. The washer nozzle create a pulsing, fan-shaped jet spray.
Headlamp-washer pump
The headlight-cleaning system is an optional extra.
The washer pump for the headlight-cleaning system is attached to the washer fluid container.
The headlight-cleaning system is activated by the junction box electronics (JBE) via a relay.
Washer-nozzle heating
The washer-nozzle heating prevents the washer nozzle freezing in cold weather.
The washer-nozzle heating is activated depending on the outside temperature (< 3 °C) by the junction box electronics. The washer-nozzle heating consists of heating resistors.
System functions
The wash / wipe system includes the following functions:
- Wipe functions
- Intermittent wipe
- Wiper speed 1
- Wiper stage 2
- Automatic wiping via rain/driving light sensor
Touring: The rear window is wiped intermittently (intermittent period is programmable by the customer, see Owner's Manual).
With the rear window opened (via rear window contact switch), no wiper operation is permitted.
With reverse gear engaged, a switch is made from intermittent operation to continuous wiping.
Wash function for windscreen and rear window (Touring)
The wash functions can be operated as of terminal 30B ON.
To operate the windscreen washer, the wiper switch is pulled backwards (towards driver).
Touring: To wash the rear window, the wiper switch must be pushed forwards (away from the driver) (speed 2).
The washer pump is activated for the activation time. If the wiper switch is activated for a very short time (< 300 ms), only the washer pump is activated. If it is actuated for a longer period, the wiper is added with a delay. After the washer pump is switched off, the windscreen is wiped for 3 wipe cycles to wipe the windscreen dry.
Headlight cleaning system
When the low beam is switched on, the headlights are washed every 10th time the windscreen washer is operated. After ignition ON and low beam ON:
The headlights are also cleaned with the 1st wash for the windscreen.
Sequence of the wash cycle:
- 0.7 seconds ON
- 1.3 seconds OFF
- 0.7 seconds ON
After headlight cleaning, no other wash cycle can be triggered for 10 minutes (anti-repeat circuit). The anti-repeat circuit is reset by terminal 30B OFF.
Safety function
The signal of the reset contact on the wiper drive (also rear window wiper on the Touring) is used as block protection for the wiper drive. If the signal is not sent by the reset contact when the wipers are switched on, the wiper drive is switched off.
Switching on the wiper again is only possible once. Thereafter, the wiper motor can only be switched on under the following conditions:
- 3 minutes have elapsed
- Terminal 30B OFF, terminal 30B ON
The wiper drive can only be switched on by actuating the wiper switch (not automatically due to the risk of injury).
With blocking protection detected, the wash pumps for the windscreen and the headlights can be activated another 3 times.
Notes for Service department
General information
Washer nozzles
The washer nozzle cannot be adjusted. The washer nozzle wet the entire windscreen (fan spray). The customer or the workshop cannot adjust the spray pattern.
Notes on coding / programming
IMPORTANT: After replacement of the wiper module, the junction box electronics (JBE) must be coded.
No liability can be accepted for printing or other faults. Subject to changes of a technical nature