3315593 - E3020 WINDSCREEN WASH/WIPE - Functional description

Functional description

The windscreen wiper control on the steering column switch unit H5 selects the various operating modes of the windscreen wash/wipe. The stalk unit H5 is supplied at pin 3 of connector D from the ignition-operated line (INT/A) of the relay R1 protected by the fuse F14 : both are contained in the junction unit B1 . The same line supplies the electronic device in the windscreen wiper motor N15 : - pin 3 of the connector B - and returns - from pin 1 of connector B - to the stalk unit H5 . The windscreen wiper motor N15 is then connected to earth - pin 1 of connector A.

Depending on the pre-selected function, the stalk unit H5 (connector D) sends the following control signals to the internal electronic device to the windscreen wiper motor N15:

  • from pin 3 of connector C for continuous fast operation: the signal reaches pin 5 of connector A of the motor N15 ;
  • from pin 1 of connector D for continuous slow operation: the signal reaches pin 4 of connector A of motor N15 ;
  • from pin 10 of connector D for intermittent/automatic operation: the signal reaches pin 2 of connector A of the motor N15 and the rain sensor K85 pin 5: this signal differs depending on the position of the intermittent function adjuster ring, which connects none, one or several resistors on the line, thus obtaining the different intermittent speeds.
When operated, the windscreen washer switch of the stalk unit H5 sends a signal from pin 5 of connector D to pin 4 of connector B of N15 : this controls the operation of the windscreen washer N20 - from pin 3 of connector A. The same signal is also sent as a command to operate the headlamp washer delay unit R3 contained in B1 - pin 20 of connector F. (  See E3022  HEADLAMP WASHER ). The system can also be connected to a rain sensor K85 which automatically adjusts the windscreen wiper sweep frequency. The sensor K85 is supplied at pin 2 from the ignition-operated line (INT/A) of relay R1 protected by the fuse F9 : both are contained in the junction unit B1 ; pin 3 is earthed. Pin 5 receives the intermittent/automatic operation signal coming from the stalk unit H5 : this enables the operation of the system and at the same time establishes the sensor's sensitivity. Pins 1 and 6 connect to the windscreen wiper motor N15 : - pin 2 connector B - indicating, in accordance with the logic described above, the type of automatic operation to be set.