BMW 7 Series: System Components

Involved Components

The following components are involved in the wiper/washer system:

• Control units
  • Steering column switch cluster
  • Central gateway module
  • Junction box electronics
  • Instrument cluster
  • Dynamic stability control
• Rain/lights/solar/condensation sensor
• Wiper switch on the steering column stalk
• Relay for headlight washer system
• Wiper motor
• Washer fluid pump
• Pump for headlight washer system
• Heated washer jets

Control Units

Steering column switch cluster

The steering column switch cluster evaluates the status of the wiper switch on the steering column stalk. The respective status is issued by the steering column switch cluster on the FlexRay.

Junction box electronics

The junction box electronics is the central control unit for all wipe and wash functions.

The junction box electronics communicate the current wipe requirement via the LIN bus. This request is received by the electronics in the wiper motor and the relevant wiper stage is initiated.

A separate relay is fitted in the front distribution box for the headlight washer system.

Dynamic stability control

The Dynamic Stability Control provides the road speed signal.

Rain/lights/solar/condensation sensor

The rain/lights/solar/condensation sensor consists of four sensors. The rain sensor is used for the wiper/washer system.

Condensation sensor

The condensation sensor consists of a sensor element with integrated processor on a flexibly mounted circuit board. The condensation sensor records the relative air humidity and the temperature on the inside of the windscreen.

The rain/lights/solar/condensation sensor is integrated in the base of the mirror and is held in place by a spring on a retaining plate. The retaining plate is securely bonded to the inside of the windscreen.

The visual connection between the rain/lights/solar/condensation sensor and the windscreen is formed by a silicone gel layer on the optical element. The condensation sensor is mounted directly on a "flexible" circuit board.

Due to the specified installation location, the flexible circuit board with the condensation sensor is pushed against the windscreen. This ensures a good thermal connection with the windscreen. A permeable membrane made from Teflon protects the condensation sensor from becoming dirty.

Fault code memory entries for the function of the rain/lights/solar/condensation sensor are stored in the junction box electronics.

If the condensation sensor fails, the junction box electronics transmits this via the KCAN2. The central gateway module transmits the information on the K-CAN. The integrated automatic heating/air-conditioning system thus receives the information and deactivates the program to prevent condensation from forming on the windscreen.

NOTE: Replacing the rain/lights/solar/condensation sensor: It is permissible to replace a rain/lights/solar/condensation sensor as long as no bubbles occur in the silicone gel layer (adhesive layer) when you do so. Please remember to initialize the sensor.

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