Ford Fiesta (2011 year). Manual — part 68

The rain sensor is built into a housing which is
mounted behind the rear view mirror on the
windshield.

The rain sensor evaluates optical conditions.
Contamination such as oil, grease or dust will
prevent correct operation. Before switching on the
automatic windshield wipers, the windshield must
be clean in the area of the rain sensor.

Windshield washers

E107102

1

2

3

4

5

Description

Item

Front washer jets

1

Washer reservoir closure

2

Description

Item

Washer reservoir

3

Washer pump

4

Rear window washer nozzle

5

Water is pumped to both the front window washer
and the rear window washer from a washer
reservoir via a washer pump.

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Wipers and Washers

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DESCRIPTION AND OPERATION

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Wipers and Washers – System Operation and Component

Description

Control Diagram

E107365

3

4

5

6

7

8

9

1

2

10

Description

Item

TCM (transmission control module)
(Vehicles with automatic transmission)

1

Instrument cluster

2

BCM (Body Control Module) input

3

Description

Item

Rear wiper motor

4

Front windshield wiper motor

5

Washer pump

6

BCM

7

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Wipers and Washers

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DESCRIPTION AND OPERATION

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Description

Item

Switch, wash/wipe system

8

Description

Item

Reversing lamp switch (vehicles with
manual transmission)

9

Combined rain sensor/light sensor

10

System Operation

The window wash/wipe system is controlled by the
BCM (Body Control Module). To do this, the BCM
primarily uses the signal from the window
wash/wipe switch. Secondary signals include the
signal from the combined rain sensor/light sensor
(optional in certain markets) and the signal of the
reversing lamp switch (vehicles with manual
transmission) or the TCM (vehicles with automatic
transmission).

Front wiper / washer system

The front window wash/wipe system will only
operate if the ignition switch is in position II.

The front and rear windshield wash/wipe systems
use a shared window washer pump and cannot be
used simultaneously.

Four wipe functions are available:

• single wipe

• intermittent wipe or automatic wipe (depending

on the vehicle specification)

• normal wipe

• fast wipe speed

The setting of the window wash/wipe switch is
transmitted to the BCM (Body Control Module).
The BCM then actuates the wiper motor via relays
and sets the wiper speed.

Normal wipe speed remains available in the event
of failure of the BCM.

Intermittent wipe

The setting of the window wiper rotary switch is
transmitted to the BCM (Body Control Module).
The BCM then actuates the wiper motor via a relay
and sets the wiper delay interval.

The window wiper rotary switch has six settings
ranging from a short delay to a long delay:

– Wiper delay in level 1 = 1.2 seconds

– Wiper delay in level 2 = 4 seconds

– Wiper delay in level 3 = 8 seconds

– Wiper delay in level 4 = 12 seconds

– Wiper delay in level 5 = 17.5 seconds

– Wiper delay in level 6 = 25 seconds

These values apply to a stationary vehicle. The
intervals are shortened with increasing vehicle
speed.

Auto

The automatic wipe function is optionally available
in some markets.

The signal from the combined rain sensor/light
sensor is transmitted via a LIN (local interconnect
network) bus to the BCM (Body Control Module),
where it is processed together with the signal from
the window wiper rotary switch which is used to
adjust the sensitivity of the sensor. The BCM then
actuates the wiper motor and sets the wiper speed
and wiper delay interval.

Front washer system

When the front washer system is switched on the
BCM (Body Control Module) switches on the
window washer pump. The BCM delays wiper
operation for 360 ms after operation of the window
washer switch. If the window washer switch is not
operated for at least 360 ms, then the BCM does
not switch on the window wiper. The BCM activates
the window wiper for as long as the window washer
switch is operated. The window washer pump is
switched off after a maximum of 10 seconds. After
clearance from the switch the BCM allows the
wipers to wipe two or three times more.

This additional wiping function allows the front
wiper blades to wipe one more time 4 seconds
after the last wiping movement to remove any
remaining water from the windshield.

The additional wiping function is activated if:

• the windshield wipers are off when the front

windshield washer system is operated

• the windshield wipers are set to intermittent

mode and have not wiped in the last 4 seconds

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Wipers and Washers

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DESCRIPTION AND OPERATION

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Rear windshield wash/wipe system

The rear window wash/wipe system will only
operate if the ignition switch is in position II.

The front and rear windshield wash/wipe systems
use a shared window washer pump and cannot be
used simultaneously.

Depending on the wiper speed of the front wipers,
the rear wipers run with a delay interval of
6 seconds, 10 seconds or continuously. The time
delay is controlled by the BCM (Body Control
Module).

The rear windshield wiper is switched on if:

• the window wash/wipe switch is in the 'rear

wiper' position

– The BCM actuates the rear wiper motor. The

windshield wiper runs in intermittent mode.

• the rear windshield washer system is operated

– The BCM switches on the rear window

washer system. The washer pump is supplied
with power. Reversing the polarity of the
pump enables the washing fluid to flow to the
rear washer jets instead of the front washer
jets. The BCM activates the window wiper
for as long as the window washer switch is
operated. The window washer pump is
switched off after a maximum of 10 seconds.
After clearance from the switch the BCM
allows the wipers to wipe two or three times
more.

• the signal "Reverse gear engaged" is received

from the reversing lamp switch or from the TCM
and the front window wash/wipe switch is in the
position for normal or fast wipe speed, or it is
set to automatic wipe (optional in certain
markets) or intermittent wipe at high speed.

– The BCM actuates the rear wiper motor until

the gear lever is moved to neutral.

Component Description

Switch, wash/wipe system

The window wash/wipe switch is a simple electrical
switch which is inserted into the steering wheel
module.

E107396

2

3

1

Description

Item

Switch, wash/wipe system

1

Window wiper rotary switch

2

Windshield washer switch

3

Switches and switch positions:

• Switch, wash/wipe system

– One-touch function downwards for single

front wipe

– 3 fixed positions upwards for front intermittent

wipe / automatic wipe (optional in some
markets), normal wipe, fast wipe

– Fixed position towards the steering wheel for

rear intermittent wipe

– One-touch function beyond the fixed position

towards the steering wheel for the rear
washer system

• Window wiper rotary switch

– 6 fixed switch positions for wiper

intervals/rain sensor sensitivity (optional in
some markets). The switch positions start
from 1 (wide symbol) at the upper end point
and end with 6 (narrow symbol) at the lower
end point

• Windshield washer switch

– One-touch function for front washer system

Rain Sensor

The rain sensor is optionally available in some
markets.

The sensor contains a number of transmitter and
receiver diodes which emit and receive infrared
light. By comparing the received signal with the
known transmitted signal, the rain sensor can
determine the moisture on the outside of the
windshield and request that the windshield wipers
are switched on.

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Wipers and Washers

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DESCRIPTION AND OPERATION

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