3239316 - E3020 WINDSCREEN WASH/WIPE - Functional description (Rear seat with central winder)
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 windscren wiper control unit
M79
,
pin A1, is also supplied by the ignition-controlled line (INT/A)
of relay
R1
protected by fuse
F14
.
Depending on the pre-selected function,
the stalk unit H5 (connector A) sends the following control signals
to the windscreen wiper motor control unit M79:
- from pin 2 for continuous fast operation: the signal reaches
pin B2 of M79 ;
- from pins 3, 4 for continuous slow and medium-fast oeration:
the signals arrive at pins B3 amd A3 of M79 ;
- from pin 5 for intermittent or automatic operation: to
pin C4 of M79 .
Windscreen wiper control unit
M79
in
turn sends signals to windscreen wiper motor
N15
to operate
the motor: from pin A8 for high speed, from pin B8 for low speed
and from pin C2 for reset control (return to rest position).
The windscreen wiper motor
N15
is
then connected to earth (pin 5). It consists of the actual geared
motor, the end of travel contacts and the electronic adjustment
and control device.
When operated, the windscreen washer switch
on the steering column switch unit
H5
sends two signals from
pin 8 and pin 9 of connector A, the first to windscreen wiper control
unit
M79
(pin A4) while the second is directly connected
to the windscreen washer pump motor
N22
. The motor is operated upon
a command from windscreen wiper control unit
M79
, from pin
B4.
The signal sent from pin 6 of stalk unit
H5
enables
operation of headlamp washers
See E3022 HEADLAMP WASHER
.
The rain sensor is connected to the control
unit at pins C3 and C7 for the power supply and earth and at pin
A2 for the actual signal. This sensor permits automatic wiper operation
when it rains.