2006 MERCEDES-BENZ SPRINTER windshield wipers

RAIN SENSOR
DESCRIPTION
The rain sensor provides the primary input for the
optional automatic wiper system (Fig. 6). The rain
sensor is located on the inside of the windshield,
where it is concealed within the molded plastic trim
cover that snaps over the base of the rear view mir-
ror arm. The sensor fits within the center of a ring-
like molded plastic bracket that is glued to the inside
of the windshield glass and that also serves as the
support for the rear view mirror.
The rain sensor is contained within a circular
molded black plastic housing with a short pigtail
wire and a connector insulator containing three ter-
minal cavities that exits one side of the housing. This
pigtail connects the rain sensor to the vehicle electri-
cal system through a dedicated take out and connec-
tor of the overhead wire harness that extends from
above the headliner. A molded plastic trough routes
and conceals the pigtail wires on the inside of the
windshield between the rear view mirror base and
the headliner.
The windshield side of the rain sensor housing is
open, but covered with a clear gelatin-like material
that protects the internal electronic sensor circuitry
and serves as the lens for the InfraRed (IR) diodes
and photocells within the sensor housing. This gel
coating must never be touched or the rain sensor
function may be impaired and the unit rendered
unusable. The rain sensor cannot be adjusted or
repaired and, if damaged or faulty, the entire sensor
must be replaced. The sensor bracket and a rear viewmirror adhesive kit are available for separate service
replacement.
OPERATION
The rain sensor operates on battery current and a
clean ground received from the rain sensor control
module. The rain sensor contains InfraRed (IR)
diodes that direct IR light beams at the windshield
at an angle. When the windshield glass is dry, most
of this IR light is reflected back to the sensor, which
uses photocell receivers to measure the intensity of
the light. When moisture accumulates on the wind-
shield glass, much of the IR light is refracted away
from the photocell receivers. This causes changes in
the signal output of the rain sensor. The rain sensor
control module monitors the signal output from the
sensor and then controls the wiper motor speed and
wipe intervals accordingly.
It is important to note that the default condition
for the wiper system is automatic wipers Off; there-
fore, if no message is received from the rain sensor
by the rain sensor control module, the automatic wip-
ers will be disabled. If automatic wipers are disabled,
normal low and high speed continuous wiper opera-
tion are unaffected. Also, due to the low voltage
nature of the rain sensor signal and the impact that
minor fluctuations in this signal strength can have
on wiper operation, grounded shielding circuits are
provided at the roof and control module connectors to
control electrical induction into the sensor signal cir-
cuit.
The hard wired rain sensor circuits may be diag-
nosed using conventional diagnostic tools and meth-
ods. However, conventional diagnostic methods may
not prove conclusive in the diagnosis of the internal
circuitry or the optics of the rain sensor. Refer to the
appropriate wiring information.
STANDARD PROCEDURE
RAIN SENSOR BRACKET REPLACEMENT
The rain sensor fits within the center of a ring-like
molded plastic bracket that is glued to the inside of
the windshield glass and that also serves as the sup-
port for the rear view mirror arm. If the bracket
should come loose from the windshield, it must be
reinstalled using a rear view mirror adhesive kit and
the procedure that follows.
Fig. 6 Rain Sensor
1 - HEADLINER
2 - TROUGH
3 - WINDSHIELD
4 - RAIN SENSOR
5 - MIRROR
8R - 12 WIPERS/WASHERSVA

(8) Reconnect the battery negative cable.
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
(1) Disconnect and isolate the battery negative
cable.
(2) Unsnap the base covers from each other and
remove them from the rear view mirror arm at the
windshield (Fig. 10).
(3) Using a small thin-bladed screwdriver, gently
pry the retaining collar slightly upward while press-
ing the mirror arm downward parallel to the wind-
shield until the mirror arm unsnaps from the
bracket.
(4) Separate and remove the two halves of the
wire cover from the rain sensor pigtail wires.(5) Loosen the screws securing both inner sun
visor hinges to the windshield header.
(6) Pull the headliner down from the windshield
header far enough to pull the rain sensor pigtail wire
connector out from under the headliner.
(7) Remove the anti-rattle felt from the wire con-
nector insulators.
(8) Disconnect the sensor pigtail wire connector
from the roof wire harness connector.
CAUTION: Do not touch the gel-like surface of the
rain sensor or the sensor function may be impaired
and the sensor rendered unusable.
(9) Remove the rain sensor from the center of the
bracket.
INSTALLATION
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
CAUTION: Do not touch the gel-like surface of the
rain sensor or the sensor function may be impaired
and the sensor rendered unusable.
(1) Position the rain sensor into the center of the
bracket on the windshield (Fig. 10).
(2) Reconnect the sensor pigtail wire connector to
the roof wire harness connector.
(3) Reinstall the anti-rattle felt over the wire con-
nector insulators.
(4) Pull the headliner down from the windshield
header far enough to tuck the rain sensor pigtail
wire connector under the headliner.
(5) Tighten the screws securing both inner sun
visor hinges to the windshield header.
(6) Align and install the two halves of the wire
cover over the rain sensor pigtail wires.
(7) Press the rear view mirror arm upward paral-
lel to the windshield until the mirror arm snaps onto
the bracket.
(8) Align and position the base covers to each
other and snap them over the rear view mirror arm
at the windshield.
(9) Reconnect the battery negative cable.
Fig. 10 Rain Sensor Remove/Install
1 - FELT
2 - CONNECTOR
3 - INNER VISOR HINGE (2)
4 - WIRE COVER
5 - BRACKET
6 - SENSOR
7 - RETAINING COLLAR
8 - BASE COVER
9 - MIRROR
10 - ARM
8R - 14 WIPERS/WASHERSVA

RAIN SENSOR CONTROL MOD-
ULE
DESCRIPTION
The Rain Sensor Control Module (RSCM) is the
primary component of the automatic wiper system
(Fig. 11). The RSCM is secured with two screws and
nuts to a bracket located under the instrument panel
above the throttle pedal within the passenger com-
partment. The rectangular molded plastic housing of
the RSCM has an integral mounting tab on each side
and an integral connector receptacle on one end,
which contains the module terminal pins. These ter-
minal pins connect the RSCM to the vehicle electrical
system through a dedicated take out and connector of
the instrument panel wiring. Concealed and pro-
tected within the RSCM housing is the electronic cir-
cuitry of the module.
The RSCM cannot be repaired and, if damaged or
faulty, the entire module must be replaced.
OPERATION
The microprocessor-based Rain Sensor Control
Module (RSCM) is only used in vehicles equipped
with an optional automatic wiper system. The RSCM
monitors inputs from the ignition switch, the wiper
and washer switch circuitry of the multi-function
switch on the steering column, the park switch
within the wiper motor, and the rain sensor on the
inside of the windshield glass. Based upon these
inputs the RSCM sends the proper control outputs to
the wiper motor and the washer pump motor to pro-
vide all of the requested wiper and washer system
functions.The RSCM operates on battery current received
from a fuse in the fuse block on a fused ignition
switch output (run-start) circuit so that the RSCM
will operate whenever the ignition switch is in the
On or Start positions. The RSCM receives ground at
all times through its connection to the instrument
panel wire harness. It is important to note that the
default condition for the wiper system is automatic
wipers Off; therefore, if no input is received from the
rain sensor by the RSCM, the automatic wipers will
be disabled and the RSCM will default the wiper and
washer system to normal manual operation for con-
tinuous low or high speed wiper or washer mode.
The hard wired RSCM circuits may be diagnosed
using conventional diagnostic tools and methods.
However, conventional diagnostic methods may not
prove conclusive in the diagnosis of the internal cir-
cuitry of the RSCM. Refer to the appropriate wiring
information.
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
(1) Disconnect and isolate the battery negative
cable.
(2) Locate the rain sensor control module on a
bracket under the instrument panel above the throt-
tle pedal (Fig. 12).
Fig. 11 Rain Sensor Control Module
1 - RAIN SENSOR CONTROL MODULE
2 - CONNECTOR RECEPTACLE
3 - MOUNTING TAB (2)
VAWIPERS/WASHERS 8R - 15

(3) Cut the tie wrap on the control module (Fig.
13).
(4) Unlock and disconnect the wire harness con-
nector from the module connector receptacle.
(5) Remove the two screws and nuts that secure
the module to the bracket.
(6) Remove the module from the bracket.
INSTALLATION
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
(1) Position the rain sensor control module to the
bracket under the instrument panel above the throt-
tle pedal (Fig. 12).
(2) Install and tighten the two screws and nuts
that secure the module to the bracket (Fig. 13).
(3) Reconnect and lock the wire harness connector
to the module connector receptacle.
(4) Install a new tie wrap to secure the wire har-
ness to the control module.
(5) Reconnect the battery negative cable.
WASHER FLUID LEVEL
SWITCH
DESCRIPTION
The optional washer fluid level switch is a single
pole, single throw switch that is integral to a unique
version of the washer pump/motor unit, located rear-
ward facing side of the washer reservoir, which is
located in a dedicated hole on the top of the sump
area near the back of the windshield washer reser-
voir on the right front fender wheel house in the
engine compartment. Only a molded plastic nipple
with a clear vent tube are visible near the top of the
washer pump/motor unit that is equipped with the
optional fluid level switch when it is installed in the
reservoir. The vent tube is routed to and retained in
an integral clip located behind the reservoir filler cap
near the top of the reservoir. This version of the
washer pump/motor unit also has a third terminal
pin in its integral connector receptacle. The washer
fluid level switch cannot be adjusted or repaired. If
faulty or damaged, the entire washer pump/motor
unit must be replaced.
OPERATION
The washer fluid level switch monitors the level of
the washer fluid in the washer reservoir. When the
fluid level in the washer reservoir is at or above the
predetermined minimum, the switch contacts are
open. When the fluid level in the washer reservoir
Fig. 12 Rain Sensor Control Module Location
1 - INSTRUMENT PANEL
2 - RAIN SENSOR CONTROL MODULE
3 - THROTTLE PEDAL
Fig. 13 Rain Sensor Control Module Remove/Install
1 - SCREW (2)
2 - CONNECTOR
3 - NUT (2)
4 - TIE WRAP
5 - MODULE
8R - 16 WIPERS/WASHERSVA

The two washer nozzles have integral mounts with
snap features that secure them near the tops of the
two wiper arms on the windshield. The lower surface
of the washer nozzle has an integral barbed nipple
that connects to the washer hose, and three nozzle
orifices are oriented to dispense the washer fluid on
the windshield glass throughout the wiped area of
the glass (Fig. 15). The washer nozzles are con-
structed entirely of molded plastic. The washer noz-
zles cannot be adjusted or repaired and, if faulty or
damaged, they must be replaced.
OPERATION
The two washer nozzles are designed to dispense
washer fluid into the wiper pattern area on the out-
side of the windshield glass. Pressurized washer fluid
is fed to each nozzle from the washer reservoir by the
washer pump/motor through rubber hoses, which are
attached to a barbed nipple on the underside of each
washer nozzle below the wiper arm. The three ori-
fices of each nozzle causes the pressurized washer
fluid to be emitted generously in several streams
throughout the travel of the wiper arm to more effec-
tively cover a larger area of the glass to be cleaned.
REMOVAL
(1) Using hand pressure, unsnap the washer noz-
zle from the wiper arm (Fig. 16).
(2) Disconnect the hose from the barbed nipple of
the washer nozzle.
INSTALLATION
(1) Reconnect the hose to the barbed nipple of the
washer nozzle (Fig. 16).
(2) Using hand pressure, slide the washer nozzle
onto the wiper arm until it snaps into place. Be cer-tain the nozzle snap feature is engaged in the locator
hole on the wiper arm.
WASHER PUMP / MOTOR
DESCRIPTION
The washer pump/motor unit is located in a dedi-
cated hole on the top of the sump area near the back
of the windshield washer reservoir on the right front
fender wheel house in the engine compartment (Fig.
17). A small permanently lubricated and sealed elec-
tric motor is coupled to the rotor-type washer pump.
An inlet nipple on the bottom of the pump housing
passes through a rubber grommet seal installed in
the dedicated mounting hole in the washer reservoir.
A small barbed outlet nipple near the bottom of the
pump housing connects the unit to the washer hose.
The washer pump/motor unit is retained on the res-
ervoir by the interference fit between the inlet nipple
and the grommet seal, which is a light press fit. An
integral electrical connector receptacle is located on
the top of the motor housing.
An optional version of the washer pump/motor unit
incorporates an integral washer fluid level switch.
This version can be distinguished from models with-
out the switch by a vent nipple at the top of the
switch housing that is connected to a vent hose that
is retained in an integral clip behind the filler cap
near the top of the reservoir, and by a third terminal
pin in the washer pump/motor connector receptacle.
The washer pump/motor unit cannot be repaired. If
faulty or damaged, the entire washer pump/motor
unit must be replaced.
Fig. 16 Washer Nozzle Remove/Install
1 - WIPER ARM
2 - WASHER NOZZLE
3 - HOSE GUARD
4 - WASHER HOSE
5 - WIPER BLADE
Fig. 17 Washer Pump/Motor
1 - INLET NIPPLE
2 - WASHER PUMP/MOTOR
3 - CONNECTOR RECEPTACLE
4 - VENT NIPPLE (W/FLUID LEVEL SWITCH ONLY)
5 - WASHER FLUID LEVEL SWITCH HOUSING
6 - OUTLET NIPPLE
VAWIPERS/WASHERS 8R - 19

OPERATION
The washer pump/motor unit is connected to the
vehicle electrical system through a single take out
and connector of the vehicle wire harness. The
washer pump/motor is grounded at all times through
a take out of the vehicle wire harness with a single
eyelet terminal connector that is secured under a
ground screw located near the right headlamp in the
engine compartment. The washer pump/motor
receives battery current on a washer switch sense
circuit through the closed contacts of the momentary
washer switch circuitry within the multi-function
switch. When the pump motor is energized, the rotor-
type pump pressurizes the washer fluid and forces it
through the pump outlet nipple, the washer plumb-
ing, and the washer nozzles onto the windshield
glass. The washer pump/motor unit can be diagnosed
using conventional diagnostic tools and methods.
REMOVAL
(1) Disconnect the vehicle wire harness connector
for the washer pump/motor from the motor connector
receptacle (Fig. 18).
(2) Disconnect the washer supply hose from the
barbed outlet nipple of the washer pump/motor and
allow the washer fluid to drain into a clean container
for reuse.(3) If the vehicle is so equipped, disconnect the
washer fluid level switch vent hose from the barbed
vent nipple near the top of the washer pump/motor
unit.
(4) Using hand pressure, firmly grasp and pull the
washer pump out of the rubber grommet seal in the
reservoir. Care must be taken not to damage the res-
ervoir.
(5) Remove the rubber grommet seal from the
washer pump mounting hole in the washer reservoir
and discard.
INSTALLATION
(1) Install a new rubber grommet seal into the
washer pump mounting hole in the washer reservoir.
Always use a new rubber grommet seal on the reser-
voir.
(2) Position the inlet nipple of the washer pump to
the rubber grommet seal in the reservoir.
(3) Using hand pressure, press firmly and evenly
on the washer pump until the inlet nipple is fully
seated in the rubber grommet seal in the washer res-
ervoir mounting hole (Fig. 18).
(4) If the vehicle is so equipped, reconnect the
washer fluid level switch vent hose to the barbed
vent nipple at the top of the washer pump/motor
housing.
(5) Reconnect the washer hose to the barbed outlet
nipple of the washer pump.
(6) Reconnect the vehicle wire harness connector
for the washer pump/motor unit to the motor connec-
tor receptacle.
(7) Refill the washer reservoir with the washer
fluid drained from the reservoir during the removal
procedure.
Fig. 18 Washer Pump/Motor Remove/Install
1 - WASHER RESERVOIR
2 - WASHER SUPPLY HOSE
3 - VENT HOSE (W/FLUID LEVEL SWITCH ONLY)
4 - WIRE HARNESS CONNECTOR
5 - WASHER PUMP/MOTOR
8R - 20 WIPERS/WASHERSVA

WIPER ARM
DESCRIPTION
The wiper arms are the rigid members located
between the wiper pivots that protrude from the cowl
top panel near the base of the windshield and the
wiper blades on the windshield glass (Fig. 23). These
wiper arms feature an over-center hinge that allows
easy access to the windshield glass for cleaning. The
wiper arm has a die cast metal pivot end with a
large tapered mounting hole at one end. A removable
molded black plastic pivot cover fits loosely over and
pivots on the wiper arm hinge pin, then snaps over
the pivot end to conceal the wiper arm retaining nut.
The wide end of a tapered, stamped steel channel
hinges on and is secured with a hinge pin to the
pivot end of the wiper arm. One end of a long, rigid,
stamped steel strap, with a small hole near its pivot
end, is riveted and crimped within the narrow end of
the stamped steel channel. The tip of the wiper blade
end of this strap is bent back under itself to form a
small hook. Concealed within the stamped steel
channel, one end of a long spring is engaged with awire hook on the underside of the die cast pivot end,
while the other end of the spring is hooked through
the small hole in the steel strap. The entire wiper
arm has a satin black finish applied to all of its vis-
ible surfaces.
Near the hook of the wiper arm steel strap is a
locating hole for the washer nozzle that is mounted
on the wiper arm. A U-shaped molded plastic guard
snaps onto the underside of the strap to conceal and
protect the washer nozzle hose. There are also two
small molded plastic washer nozzle hose routing
brackets clipped onto the underside of the wiper arm
pivot end.
The wiper arms for this model are unequal in
length, with the longer arm being installed on the
left (driver) side of the windshield. A wiper arm can-
not be adjusted or repaired. If damaged or faulty, the
entire wiper arm unit must be replaced. The washer
nozzle, nozzle hose, routing brackets, and pivot end
Fig. 23 Wiper Arm
1 - HOOK 7 - CHANNEL
2 - STRAP 8 - COVER
3 - WASHER HOSE 9 - PIVOT END
4 - BRACKET (2) 10 - GUARD
5 - HINGE PIN 11 - WASHER NOZZLE
6 - TENSION SPRING
VAWIPERS/WASHERS 8R - 23

cover are available for individual service replace-
ment.
OPERATION
The wiper arms are designed to mechanically
transmit the motion from the wiper pivots to the
wiper blades. The wiper arm must be properly
indexed to the wiper pivot in order to maintain the
proper wiper blade travel on the glass. The tapered
mounting hole in the wiper arm pivot end interlocks
with the serrations on the outer circumference of the
wiper pivot shaft, allowing positive engagement and
finite adjustment of this connection. The mounting
nut locks the wiper arm to the threaded end of the
wiper pivot shaft. The spring-loaded wiper arm hinge
controls the down-force applied through the tip of the
wiper arm to the wiper blade on the glass. The hook
formation on the tip of the wiper arm provides a cra-
dle for securing and latching the wiper blade pivot
block to the wiper arm.
REMOVAL
(1) Disconnect the washer nozzle hose from the
elbow fitting on the cowl top panel near the pivot end
of the wiper arm (Fig. 24).
CAUTION: The use of a screwdriver or other prying
tool to remove a wiper arm may distort it. This dis-
tortion could allow the arm to come off of the wiper
pivot during wiper operation, regardless of how
carefully it is reinstalled.
(2) Unsnap the end of the pivot cover from the
wiper blade pivot end, then pull the cover away from
the wiper arm hinge pin to remove the cover from
the wiper blade.(3) Remove the nut that secures the wiper arm to
the wiper pivot shaft.
(4) If necessary, use a suitable battery terminal
puller to disengage the wiper arm from the wiper
pivot shaft (Fig. 25).
(5) Remove the wiper arm pivot end from the
wiper pivot shaft.
INSTALLATION
NOTE: Be certain that the wiper motor is in the park
position before attempting to install the wiper arms.
Turn the ignition switch to the On position and
move the right (wiper) control stalk of the multi-
function switch to its Off position. If the wiper piv-
ots move, wait until they stop moving, then turn the
ignition switch back to the Off position. The wiper
motor is now in its park position.
NOTE: The wiper arms and wiper blades for this
model are both unequal in length, with the longer
arm and blade being installed on the left (driver)
side of the windshield.
(1) The wiper arms must be indexed to the wiper
pivot shafts with the wiper motor in the park posi-
tion to be properly installed. Position the wiper arm
pivot ends onto the wiper pivots so that the lower
edge of the wiper arm tip is aligned with the black
wiper alignment line located near the lower edge of
the windshield glass (Fig. 24).
(2) Once the wiper blade is aligned, lift the wiper
arm away from the windshield slightly to relieve the
spring tension on the pivot end and push the pivot
hole in the pivot end of the arm down firmly and
evenly over the wiper pivot shaft. Gently lower the
wiper arm until the wiper blade rests on the glass.
Fig. 24 Wiper Arm Remove/Install
1 - PIVOT COVER
2 - NUT
3 - PIVOT SHAFT
4 - WASHER NOZZLE HOSE
5 - ELBOW FITTING
6 - WIPER ARM
Fig. 25 Wiper Arm Puller - Typical
1 - WIPER ARM
2 - WIPER PIVOT SHAFT
3 - BATTERY TERMINAL PULLER
8R - 24 WIPERS/WASHERSVA