Chrysler Town, Dodge Caravan. Manual - part 139

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.

REAR WIPER/WASHER SYSTEM

When continuous rear wiper operation is required,

the BCM will provide ignition ON voltage to the rear
wiper motor. When the wiper switch is turned OFF,
the BCM provides circuit ground to operate the
motor until the wipe cycle is complete and the wiper
arm returns to the base of the rear window.

When intermittent rear wiper mode is selected, the

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

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.

• 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.

8R - 2

WIPERS/WASHERS

WIPERS/WASHERS (Continued)

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.

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.

WIPERS/WASHERS

8R - 3

WIPERS/WASHERS (Continued)

DIAGNOSIS AND TESTING - REAR WIPER
SYSTEM

The rear window wiper system operates in several

modes:

• Continuous wipe

• Intermittent wipe

• Wash

• Wipe after wash

The windshield wiper circuits are continuously

t scan tool.

DIAGNOSIS AND TESTING - WASHER SYSTEM

WASHER SYSTEM DIAGNOSIS

CONDITION

POSSIBLE CAUSES

CORRECTION

WASHER MOTOR

1. IPM FUSE #33 BLOWN OR
DEFECTIVE.

1. CHECK FUSE #33 IN THE IPM.
REPLACE IF NOT OK.

2. IPM FUSE #33 LOOSE.

2. PROPERLY INSTALL IPM FUSE #33 IN
SOCKET.

BLOWN FUSE WHEN
IGNITION SWITCH IS IN
THE RUN OR ACCESSORY
POSITION.

1. SHORT IN IPM BETWEEN
FUSE #33 AND PIN 11 OR PIN
1.

1. REFER TO IPM DIAGNOSTIC
PROCEDURES IN WIRING DIAGRAMS.

2. SHORT IN MOTOR POWER
CIRCUIT.

2. SHORT OR DEFECTIVE CIRCUIT
BETWEEN IPM PIN 11 AND WASHER
MOTOR CONNECTOR POSITIVE
TERMINAL 2. IF NOT OK, REPAIR CIRCUIT.

3. SHORT IN WASHER PUMP
MOTOR.

3. REPLACE WASHER PUMP MOTOR.

WASHER MOTOR RUNS
WHEN IGNITION SWITCH
IN RUN OR ACCESSORY
POSITION.

1. SHORT IN IPM BETWEEN
WASHER PUMP MOTOR LSD
AND PIN 20.

1. REFER TO IPM DIAGNOSTIC
PROCEDURES IN WIRING DIAGRAMS.

2. DEFECTIVE FRONT
WASHER LSD IN IPM.

2. REFER TO IPM DIAGNOSTIC
PROCEDURES IN WIRING DIAGRAMS.

3. SHORT IN MOTOR GROUND
CIRCUIT.

3. SHORT OR DEFECTIVE CIRCUIT
BETWEEN IPM PIN 20 AND MOTOR
CONNECTOR NEGATIVE TERMINAL 1. IF
NOT OK, REPAIR CIRCUIT.

8R - 4

WIPERS/WASHERS

WIPERS/WASHERS (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

WASHER SYSTEM WILL
NOT FLOW WASHER
FLUID.

1. NO WASHER FLUID IN
RESERVOIR.

1. FILL WASHER RESERVOIR.

2. IPM FUSE #33 BLOWN.

2. SHORT OR DEFECTIVE CIRCUIT
BETWEEN IPM PIN 11 AND WASHER
PUMP MOTOR CONNECTOR POSITIVE
TERMINAL 2. INTERNAL SHORT IN IPM. IF
NOT OK, REPAIR CIRCUIT OR REFER TO
IPM DIAGNOSTIC PROCEDURES IN
WIRING DIAGRAMS.

3. WASHER HOSE NOT
FLOWING WASHER FLUID.

3. ASSURE WASHER HOSE IS NOT
PINCHED, LOOSE, BROKEN OR
DISCONNECTED. IF NOT OK, PROPERLY
ROUTE OR REPAIR WASHER HOSE.

4. MOTOR CONNECTOR
LOOSE.

4. PROPERLY SEAT AND LOCK
CONNECTOR TO MOTOR.

5. MOTOR CONNECTOR
TERMINALS BENT.

5. REPAIR TERMINALS AND PROPERLY
SEAT CONNECTOR TO MOTOR.

6. OPEN CIRCUIT TO OR
FROM WASHER SELECT
SWITCH.

6. OPEN OR DEFECTIVE CIRCUIT
BETWEEN IPM BODY CONTROLLER PIN
27 AND WASHER SELECT SWITCH PIN 4,
OR OPEN OR DEFECTIVE CIRCUIT
BETWEEN IPM BODY CONTROLLER PIN
22 AND WASHER SELECT SWITCH PIN 2.
IF NOT OK, REPAIR CIRCUIT.

7. OPEN OR DEFECTIVE
WASHER SELECT SWITCH.

7. (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/MULTI-FUNCTION
SWITCH - DIAGNOSIS AND TESTING).

8. OPEN POWER CIRCUIT TO
MOTOR.

8. OPEN OR DEFECTIVE CIRCUIT
BETWEEN IPM CONNECTOR TERMINAL 11
AND WASHER MOTOR CONNECTOR
POSITIVE TERMINAL 2. INTERNAL OPEN
IN IPM. IF NOT OK, REPAIR CIRCUIT OR
REFER TO IPM DIAGNOSTIC
PROCEDURES IN WIRING DIAGRAMS.

9. OPEN OR DEFECTIVE
MOTOR GROUND CIRCUIT.

9. OPEN OR DEFECTIVE CIRCUIT
BETWEEN IPM CONNECTOR TERMINAL
20 AND WASHER MOTOR CONNECTOR
NEGATIVE TERMINAL 1. INTERNAL OPEN
IN IPM. IF NOT OK, REPAIR CIRCUIT OR
REFER TO IPM DIAGNOSTIC
PROCEDURES IN WIRING DIAGRAMS.

10. OPEN CIRCUIT IN MOTOR.

10. CHECK FOR OPEN CIRCUIT IN MOTOR
BETWEEN POSITIVE TERMINAL 2 AND
NEGATIVE TERMINAL 1. IF NOT OK,
REPLACE WASHER MOTOR.

11. SEIZED MOTOR BEARINGS.

11. APPLY DIRECT BATTERY VOLTAGE TO
MOTOR TERMINALS. IF MOTOR DOES
NOT RUN, REPLACE MOTOR.

WIPERS/WASHERS

8R - 5

WIPERS/WASHERS (Continued)

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