windshield wiper switch when the ignition switch is
in the RUN or ACCESSORY positions. The wind-
shield wiper system is protected by a 30 amp fuse (9)
located in the Power Distribution Center (PDC) part
of the Integrated Power Module (IPM) in the engine
compartment. The wiper/washer switch is integral to
the multi-function switch. It is a resistive MUX
switch that sends inputs to the BCM to operate the
wiper/washer system.

REAR WIPER/WASHER SYSTEM

The rear windshield wiper and washers can be

operated when the ignition switch is in the RUN
position.

If equipped with Manual Temperature Controls

(MTC), the rear wiper/washer switch is integral to
the HVAC control unit. It replaces what was formerly
the ON/OFF switch. If equipped with Automatic Tem-
perature Controls (ATC), the rear wiper/washer
switch is located on the accessory switch panel in the
center stack of the instrument panel.

WIPERS/WASHERS

8R - 1

OPERATION

FRONT WIPER/WASHER SYSTEM

The windshield washer circuit is protected by a 15

amp Cartridge Fuse located in the IPM. The wiper
motor has permanent magnetic fields. The speeds are
determined by current flow to the appropriate set of
brushes inside the motor. The current flow is con-
trolled by the multi-function switch. The high speed/
low speed relays are located in the IPM. The speed
sensitive intermittent wiper is controlled by the Body
Control Module (BCM). The intermittent mode, with
the vehicle traveling greater than 10.4 mph, has a
range of 0.5 to 18 seconds. With the vehicle traveling
less than 10.4 mph, the time delay doubles to a
range of 1 to 36 seconds. The wiper arms will park at
the base of the windshield just above the cowl cover
after the wiper switch is turned OFF.

The windshield wiper motor and linkage is located

in an integral wiper unit at the rear of the engine
compartment. The wiper unit must be removed to
gain access to the wiper motor.

The front and rear washer systems share the same

washer pump motor.

REAR WIPER/WASHER SYSTEM

When rear wiper operation is required, the BCM

will provide ignition ON voltage to the rear wiper
motor (Export and ATC equipped vehicles only).
When the wiper switch is turned OFF, the BCM pro-
vides circuit ground to operate the motor until the
wipe cycle is complete and the wiper arm returns to
the base of the rear window.

Switch only offers an intermittent rear wiper

mode. The wiper motor will cycle every 7 seconds.
The intermittent delay time is also adjusted based
upon vehicle speed. With the vehicle traveling
greater than 50 mph, the cycle changes to every 5
seconds.

When rear washer is requested by depressing and

holding down the switch, the BCM then provides a
ground for the washer motor. Until the switch is
released, the motor will be in a continuous wipe
mode, then return to an intermittent wipe mode.

DIAGNOSIS AND TESTING

DIAGNOSIS AND TESTING - FRONT WIPER
SYSTEM

The windshield wiper system operates in several

modes:

• Low and high speed normal wipe

• Speed sensitive intermittent wipe

• Wipe after wash

• Park (switch OFF)

The windshield wiper circuits are continuously

monitored and controlled by the Body Control Mod-
ule (BCM). If a problem occurs in the electronic com-
ponents, wiring, switch (except integral motor park
switch) and wiper motor a Diagnostic Trouble Code
(DTC) will be stored in the BCM memory. DTC’s can
be retrieved using a DRB III

t scan tool. Refer to the

proper Body Diagnostic Procedures manual for DTC
descriptions and retrieval information.

The windshield wiper park switch and circuit is

monitored by the BCM. The park switch and circuit
can be tested using the Wiper System Diagnosis
table.

DIAGNOSIS AND TESTING - FRONT
WIPER/WASHER SWITCH

(1) Remove the multi-function switch (Refer to 8 -

ELECTRICAL/LAMPS/LIGHTING

EXTERIOR/

MULTI-FUNCTION SWITCH - REMOVAL).

(2) Using an ohmmeter check resistance readings

between switch pins. Refer to the WIPER/WASHER
SWITCH RESISTANCE table.

WIPER/WASHER SWITCH RESISTANCE

SWITCH POSITION

RESISTANCE BETWEEN

OFF

1 AND 2 = 23.9K

± 5%

DELAY POSITION

1ST

1 AND 2 = 7.9K

± 5%

2ND

1 AND 2 = 4.6K

± 5%

3RD

1 AND 2 = 2.9K

± 5%

4TH

1 AND 2 = 1.9K

± 5%

5TH

1 AND 2 = 1.3K

± 5%

LOW

1 AND 2 = 670

± 5%

HIGH

1 AND 2 = 240

± 5%

WASH

1 AND 4 = 5.9K

± 5%

DIAGNOSIS AND TESTING - FAILED PARK
SWITCH

If the wiper park switch has failed, the windshield

wipers will operate as follows:

• SWITCH OFF - Wipers stop in current location

regardless of the park signal.

• INTERMITTENT MODE - Wipers operate con-

tinuously or at low speed for one or more extra
wipes.

• LOW SPEED - Wipers operate at low speed.

• HIGH SPEED - Wipers operate at high speed.

8R - 2

WIPERS/WASHERS

WIPERS/WASHERS (Continued)

• WIPE AFTER WASH - Wipers operate at low

speed in any mode setting. Wipers operate only while
the wash button is depressed with switch in the OFF
mode and wipers stop in mid-cycle when button is
released.

The windshield wiper park switch and circuit is

monitored by the BCM. The park switch and circuit
can be tested using the WIPER SYSTEM DIAGNO-
SIS table.

WIPER SYSTEM DIAGNOSIS

CONDITION

POSSIBLE CAUSES

CORRECTION

WIPER BLADES DO NOT
PARK PROPERLY

1. WIPER ARMS IMPROPERLY
PARKED.

1. REMOVE WIPER ARMS AND REPARK.
REFER TO WIPER ARM REMOVAL AND
INSTALLATION.

2. WIPER ARMS ARE LOOSE ON
PIVOT SHAFT.

2. REMOVE WIPER ARM AND REPARK.
REFER TO WIPER ARM REMOVAL AND
INSTALLATION.

3. MOTOR CRANK LOOSE AT
OUTPUT SHAFT.

3. REMOVE WIPER ARM, RUN WIPER
MOTOR TO PARK POSITION AND
REMOVE THE MODULE. WITHOUT
ROTATING THE MOTOR OUTPUT SHAFT,
REMOVE THE CRANK AND CLEAN ANY
FOREIGN MATTER FROM THE MOTOR
SHAFT. INSTALL THE MOTOR CRANK IN
ITS ORIGINAL POSITION.

4. STRIPPED WIPER ARM HEAD.

4. REPLACE WIPER ARM.

MOTOR STOPS IN ANY
POSITION WHEN THE
SWITCH IS TURNED OFF

OPEN PARK CIRCUIT.

CHECK PARK SWITCH BY
DISCONNECTING THE WIRE
CONNECTOR AND APPLY BATTERY
VOLTAGE TO PIN 4. PLACE A JUMPER
WIRE FROM PIN 2 TO PIN 3 AND THEN
TO AN EXTERNAL GROUND. REPLACE
MOTOR IF MOTOR DOES NOT PARK.

MOTOR WILL NOT STOP
WHEN THE SWITCH IS
TURNED OFF

1. FAULTY SWITCH.

1. CHECK SWITCH IN LOW, HIGH AND
INTERMITTENT POSITION.

2. LACK OF DYNAMIC BRAKE ON
WET GLASS.

2. ENSURE PARK SWITCH HAS CLEAN
GROUND.

WIPER BLADES SLAP
AGAINST COWL SCREEN
OR WINDOW MOLDINGS.

WIPER ARMS ARE PARKED
INCORRECTLY.

PARK WIPER ARMS. REFER TO WIPER
ARM ADJUSTMENT.

BLADES CHATTER

1. FOREIGN SUBSTANCE SUCH
AS POLISH ON GLASS OR
BLADES.

1. CLEAN GLASS AND BLADE ELEMENT
WITH NON-ABRASIVE CLEANER.

2. ARMS TWISTED, BLADE AT
WRONG ANGLE ON GLASS.

2. REPLACE ARM.

3. BLADE STRUCTURE BENT.

3. REPLACE BLADE.

4. BLADE ELEMENT HAS
PERMANENT SET.

4. REPLACE BLADE.

WIPERS/WASHERS

8R - 3

WIPERS/WASHERS (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

WIPER KNOCK AT
REVERSAL

1. LINKAGE BUSHINGS WORN.

1. REPLACE WORN LINK. REFER TO
WIPER LINKAGE REMOVAL AND
INSTALLATION.

2. ARMATURE ENDPLAY IN
MOTOR.

2. REPLACE WIPER MOTOR. REFER TO
WIPER MOTOR REMOVAL AND
INSTALLATION.

WIPER MOTOR WILL NOT
RUN

1. BLOWN FUSE.

1. REPLACE FUSE, AND RUN SYSTEM.

2. NEW FUSE BLOWS.

2. CHECK FOR SHORT IN WIRING OR
SWITCH.

3. NEW FUSE BLOWS.

3. REPLACE FUSE, REMOVE MOTOR
CONNECTOR, TURN SWITCH ON, FUSE
DOES NOT BLOW, REPLACE MOTOR.

4. NO VOLTAGE AT MOTOR.

4. CHECK SWITCH AND WIRING
HARNESS. REFER TO WIRING
DIAGRAMS.

5. POOR GROUND.

5. REPAIR GROUND WIRE CONNECTION
AS NECESSARY.

DIAGNOSIS AND TESTING - REAR WIPER
SYSTEM

The rear window wiper system operates in several

modes:

• Continuous wipe (Export and ATC equipped

vehicles only)

• Intermittent wipe

• Wash

• Wipe after wash
The windshield wiper circuits are continuously

t scan tool.

8R - 4

WIPERS/WASHERS

WIPERS/WASHERS (Continued)

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