Ford Fiesta (2011 year). Manual — part 69

E92596

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2

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Description

Item

Raindrop

1

LED
Comments:

(transmitter diode)

2

Lens

3

Photodiode
Comments:

(receiver diode)

4

Light loss due to deflection

5

The LED emits a beam of light with a known
intensity. The emitted beam emerges through the
lens and is then reflected by the windshield.

The reflected light beam enters back through the
lens and then reaches the photodiode. The
corresponding value taken without moisture on the
windshield is used as the reference value for
automatic calibration.

Subsequent deviations from this value cause the
windshield wipers to be switched on.

If precipitation falls on the windshield, part of the
light beam is deflected. This reduces the intensity
of the light reflected by the windshield. This loss
of intensity is registered by the photodiode and
reported via an LIN signal to the BCM (Body
Control Module).

When the automatic wipe function is switched on
(window wash/wipe lever set to intermittent wiping)
the wipers are only activated automatically if the
rain sensor registers water on the windshield.

The sensitivity of the rain sensor can be changed
by adjusting the window wiper rotary switch.

• Window wiper rotary switch at the top corner:

high sensitivity

– The wipers wipe even if only a small amount

of water has been measured on the
windshield.

• Window wiper rotary switch at the bottom

corner: low sensitivity

– The wipers only wipe if a large amount of

water has been measured on the windshield.

The rain sensor is self-calibrating.

The rain sensor supplies LIN signals with values
between 0 and 7 to the BCM (Body Control
Module).

Meaning of signals from rain sensor:

• Signal "0": window is dry.

• Signal "1-5": Windshield is damp. The BCM

activates normal wiping.

• Signal "6-7": Windshield is receiving severe

precipitation. The BCM activates the fast wipe
speed whenever the signal value is greater than
4.

Front windshield wiper motor

The front windshield wiper motor is a DC motor
with 3 brush type contacts. One brush type contact
is for ground and one is for normal wiping speed.
The third brush type contact is activated for high
wiping speed.

The integrated home switch is directly connected
to the BCM (Body Control Module). The home
switch contacts are open in all wiper motor
positions except the home position. When the
home switch contacts are open, the wiper motor
remains switched on even if a signal from the
steering wheel module requests that the wipers
stop. In home position, the home switch contacts
create a ground connection. The BCM recognizes
this ground connection and switches the wiper
motor off.

Rear wiper motor

The rear windshield wiper motor is a DC motor with
2 brush type contacts. It is controlled by a voltage
supply.

The integrated home switch is directly connected
to the BCM (Body Control Module). The home
switch contacts are closed in all wiper motor
positions except the home position. When the

G1079966en

501-16-

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Wipers and Washers

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DESCRIPTION AND OPERATION

201

home switch contacts are closed, the wiper motor
is supplied with a voltage by the BCM. When the
wiper motor reaches the home position, the home
switch contacts are opened and the power supply
is interrupted by the BCM. While the window
wash/wipe switch remains in the "rear washer"
position, the wiper motor is again supplied with a
voltage by the BCM and continues to run. This
process is repeated during every revolution of the
wiper motor.

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DESCRIPTION AND OPERATION

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Wipers and Washers

schematic and connector information.

General Equipment

Ford diagnostic equipment

Inspection and Verification

NOTE: Before retrieving the vehicle-specific data
make sure that all electrical connections in the
vehicle are reconnected so that the module and
the Ford diagnostic equipment can communicate
correctly.

NOTE: If a new generic electronic module (GEM)
is being installed, the new module must be
configured following installation. For this purpose,
the vehicle-specific data is retrieved from the
module to be changed using the Ford diagnostic
equipment and is transferred to the new module.

1. Verify the customer concern.

2. Visually check for any obvious mechanical or

electrical damage.

Visual Inspection Chart

Electrical

Mechanical

• Fuse(s)

• Connectors

• Wiring harness

• Washer pump

• Front/rear window

wiper motor

• Wiper blade(s)

• Rotating shaft –

wiper arm

• Washer reservoir

• Hose(s)

• Nozzles

• Check the

passenger-side
windshield wiper for
residue-free wiping
in the vicinity of the
rain sensor.

• Check the adhesive

pad between the
rain sensor and the
windshield for
trapped air.

• Clean wax residues

from the windshield
in the vicinity of the
rain sensor.

• Check the wind-

shield for
damage/cracks in
the vicinity of the
rain sensor.

• Check that the rain

sensor retaining
frame is correctly
attached to the
windshield.

3. If an obvious cause for an observed or reported

concern is found, correct the cause (if possible)
before proceeding to the next step.

4. If the cause is not visually evident, verify the

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DIAGNOSIS AND TESTING

Refer to Wiring Diagrams

Section 501-16, for

symptom and refer to the

Ford diagnostic

equipment

to diagnose the system.

201

Windshield Wiper Blade and Pivot Arm Adjustment

Special Tool(s)

501-027
Aligner, Wiper Arm

ES32006

501-027-01
Adapter for 501-027

E73710

Adjustment

1.

CAUTION: Make sure that the motor is
in the park position.

E77631

2. NOTE: The angle of the wiper on the scale must

point from the zero center line to the center of
the windshield/rear window. Ignore the
plus/minus (+/-) signs on the adjusting tool.

NOTE: Make sure that the 3 marked points of
the special tool are in contact with the glass.

Using the special tool, read off the angle
between the wiper arm and the glass.

Special Tool(s): 501-027, 501-027-01

E73759

501-027

501-027-01

3.

CAUTION: Make sure that the special
tool is lifted off the glass when adjusting
the angle.

Adjust the wiper arm to an angle of 5°±2°.

E115857

4.

E77670

501-027

501-027-01

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GENERAL PROCEDURES

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