The electronic device inside the steering column switch unit H005 is supplied at pin 2 of connector A by the line contrlled by the ignition (INT) protected by fuse F51 of the junction unit under the dashboard B002.According to the function selected (windscreen wiping and/or washing), the steering column switch unit H005 (connector A) sends the following signals to the windscreen wiper control unit M079 (electro-mechanical and electronic control unit integrated in the windscreen wiper motor):
from pin 9 for continuous slow operation (first speed) to pin 8;
from pin 8 for continuous slow operation (first speed) to pin 7;
from pin 11 for intermittent operation, determined by the steering column switch unit or the rain sensor, to pin 5;
from pin 12 for the activation of the windscreen washer pump to pin 6.
The windscreen wiper control unit M079 is supplied at pin 1 directly by the battery via the relay R12 and fuse F43, both housed in the junction unit under the dashboard B002. The windscreen washer pump, interfaced at the front/headlamp washer coupling D098, is supplied from pin 3 of control unit M079 at pin 4.The signal for enabling the intermitten function via the rain and dusk sensor K125, is sent via the A-BUS line from pin 10 of the windscreen wiper control unit M079.If the windscreen washer fluid level inside the reservoir is insufficient, then the info-telematic control unit M065 receives a negative signal, at pin 21 of connector A, from the switch interfaced with the front/headlamp washer coupling D098 (pin 2); this signal is sent via the B-CAN (pins 1 and 3 of connector A) to the instrument panel E050 (pins 3 and 4 of connector A) which displays the message and the symbol.Body Computer M001 receives an INT/A (key-on) signal from ignition switch H001 at pin 27 of connector D via fuse F31 of underfacia control unit B002.The Body Computer M001 also acquires information concerning the on/off status of the windscreen wiper and a possible failure of the rain sensor through the same line.These signals are transmitted via the B-CAN for other functions; the instrument panel E050 shows the failure of the sensor on the display thanks to the signals acquired at pins 3 and 4 of connector A.