Chrysler Town, Dodge Caravan. Manual - part 95

switch in the HVAC control assembly and a relay
with timer switch to turn OFF the system after ten
minutes. The main feed circuit is protected by fuse
13 (40 amp) in the Power Distribution Center (PDC)
which is connected directly to the front control mod-
ule (FCM) to form an integrated unit called an Inte-
grated Power Module (IPM). The rear defogger
switch and relay also activates the heated power side
view mirrors. The rear defogger switch also activates
the heated windshield wiper de-icer which is powered
by the RUN/ACC relay in the IPM and feed thru fuse
#11 (20 amp) in the PDC. The heated mirror circuit
is protected by a non-servicable Positive Temperature
Coefficient (PTC) located inside the PDC. The heated
windshield wiper de-icer circuit is protected by fuse
11 (20 amp) in the PDC.

The Heated Windshield Wiper Deicer is also acti-

vated when the DEFROST mode is selected on the
HVAC. In the DEFROST mode the rear defogger
timout is bypassed, the heated windshield wiper de-
icer will stay ON until another mode is selected. For
circuit information and component location refer to
appropriate section for Wiring Diagrams.

CAUTION:
Since grid lines can be damaged or scraped off by
sharp instruments, care should be taken in cleaning
the glass or removing foreign materials, decals or
stickers. Normal glass cleaning solvents or hot
water used with rags or toweling is recommended.

DEFOGGER RELAY

DESCRIPTION

There is no heated windshield wiper de-icer relay.

The grid is powered directly from fuse #11 in the
PDC and is controlled directly from the HVAC con-
trol assembly.

REAR WINDOW DEFOGGER
GRID

STANDARD PROCEDURE - GRID LINE REPAIR
REAR

For Grid repair procedure for the rear window

defogger

(Refer

ELECTRICAL/HEATED

GLASS/WINDSHIELD GRID - STANDARD PROCE-
DURE).

REAR WINDOW DEFOGGER
SWITCH

DESCRIPTION

The rear window defogger switch is integrated into

the HVAC control panel assembly (Fig. 3)

OPERATION

A LED indicator will illuminate when the switch is

activated. The switch energizes the HVAC control
assembly when it requests the Front Control Module
(FCM) to activate the rear window defogger relay.
The relay controls the current to flow to the grids of
the rear window defogger, heated power side view
mirrors. The defogger relay will be on for approxi-
mately 10 minutes or until the control switch or igni-
tion is turned off.

Fig. 3 HVAC CONTROL PANEL

1 - TRIM BEZEL
2 - ACT SENSOR
3 - A/C REQUEST SWITCH
4 - REAR WINDOW DEFOGGER/HEATED MIRRORS SWITCH
COMBO
5 - FRONT WINDOW DEFROSTER MODE SELECTOR

8G - 2

HEATED GLASS

HEATED GLASS (Continued)

WINDSHIELD GRID

DIAGNOSIS AND TESTING - SYSTEM TEST

Electrically heated rear window defogger or the

heated windshield wiper deicer operation can be
checked on the vehicle in the following manner:

(1) Turn the ignition switch to the ON position.
(2) Using a ammeter on the battery, turn the rear

defogger control switch to the ON position, a distinct
increase in amperage draw should be noted.

(3) The rear window defogger or the heated wind-

shield wiper deicer operation can be checked by feel-
ing the glass. A distinct difference in temperature
between the grid lines and adjacent clear glass can
be detected in 3 to 4 minutes of operation.

(4) Using a DC voltmeter (Fig. 4) contact terminal

B with the negative lead, and terminal A with the
positive lead. The voltmeter should read 10-14 volts.

(5) Indicator light illumination means that there is

power available at the switch only and does not nec-
essarily verify system operation.

(6) If turning the defogger switch ON, no distinct

current draw on the ammeter the problem should be
isolated in the following manner:

• Confirm that ignition switch is ON.

• Ensure that the heated rear window or the

heated windshield wiper deicer feed pigtail is con-
nected to the wiring harness and that the ground
pigtail is in fact grounded.

• Ensure that the proper fuse in the PDC is OK.
(7) When the above steps have been completed and

the system is still inoperative it may be necessary to
connect a DRBIII scan tool and refer to the Diagnos-
tic Service Manual, you may also check for the fol-
lowing being defective:

• HVAC control assembly

• Rear window defogger relay in the PDC portion

of the IPM.

• Rear window defogger relay control circuity in

the FCM portion of the IPM.

• Check for loose connector or a wire pushed out

of connector.

• Rear window or the windshield grid lines (all

grid lines would have to be broken, or one of the feed
pigtails not connected to the bus bar, for no ammeter
deflection).

(8) If turning the switch ON produces severe volt-

meter deflection, the circuit should be closely checked
for a shorting condition.

(9) If the system operation has been verified but

indicator LED does not light, replace the HVAC con-
trol assembly.

(10) For detailed wiring information, refer to the

appropriate section for Wiring Diagrams.

STANDARD PROCEDURE - GRID LINE AND
TERMINAL REPAIR

WARNING: REPAIR KIT MAY CAUSE SKIN OR EYE
IRRITATION. CONTAINS EPOXY RESIN AND AMINE
TYPE

HARDENER,

HARMFUL

SWALLOWED.

AVOID CONTACT WITH SKIN AND EYES. FOR SKIN,
WASH AFFECTED AREAS WITH SOAP AND WATER.
DO NOT TAKE INTERNALLY. IF TAKEN INTER-
NALLY, INDUCE VOMITING; CALL A PHYSICIAN
IMMEDIATELY. IF IN CONTACT WITH EYES, FLUSH
WITH PLENTY OF WATER. USE WITH ADEQUATE
VENTILATION. DO NOT USE NEAR FIRE OR FLAME.
CONTENTS

CONTAINS

FLAMMABLE

SOL-

VENTS. KEEP OUT OF REACH OF CHILDREN.

The repair for the front windshield or the rear win-

dow grids are the same.

The repair of grid lines and replacement of the ter-

minal is possible using the Mopar

t Repair Package

or equivalent.

(1) Clean area surrounding grid line or terminal

by gently rubbing area with steel wool.

(2) Wipe area with clean cloth soaked in alcohol or

similar solvent. It is necessary that all contaminants
be removed from repair area.

(3) Remove package separator clamp and mix plas-

tic conductive epoxy thoroughly.

(4) For grid line, mark off area to be repaired with

masking tape (Fig. 5).

(5) Apply conductive epoxy through slit in masking

tape. Overlap both ends of the break.

Fig. 4 Grid Line Test

1 - VOLTMETER
2 - TERMINAL B
3 - FEED WIRE
4 - MID-POINT C (TYPICAL)
5 - HEATED REAR WINDOW GRIDS
6 - GROUND WIRE
7 - TERMINAL A

HEATED GLASS

8G - 3

(6) For a terminal replacement, apply a thin layer

of epoxy to area where terminal was fastened.

(7) Apply a thin layer of epoxy on terminal and

place terminal on desired location. To prevent termi-
nal from falling off use a wooden wedge to secure it.

(8) Carefully remove masking tape from grid line.

CAUTION: Do not allow the laminated windshield
glass surface to exceed 82° C (180° F) or the glass
may fracture. The rear window glass surface should
not exceed 204° C (400° F).

(9) Allow epoxy to cure 24 hours at room tempera-

ture.

(10) After epoxy is properly cured remove wedge

from terminal and check the operation of the rear
window defogger.

Fig. 5 Grid Line Repair

1 - BREAK
2 - GRID LINE
3 - MASKING TAPE

8G - 4

HEATED GLASS

WINDSHIELD GRID (Continued)

HEATED MIRRORS

TABLE OF CONTENTS

page

HEATED MIRRORS

DESCRIPTION

. . . . . . . . . . . . . . . . . . . . . . . . . . 5

OPERATION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

DIAGNOSIS AND TESTING - HEATED

MIRROR TEST

. . . . . . . . . . . . . . . . . . . . . . . . 5

MIRROR SWITCH

DESCRIPTION

. . . . . . . . . . . . . . . . . . . . . . . . . . 5

OPERATION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

HEATED MIRROR GRID

STANDARD PROCEDURE - HEATED MIRROR

. . 6

RELAY

DESCRIPTION

. . . . . . . . . . . . . . . . . . . . . . . . . . 6

HEATED MIRRORS

DESCRIPTION

Heated mirrors are available on models with

Power Mirrors and Rear Window Defogger only.

OPERATION

The heated mirror is controlled by the rear window

defogger switch. The heated mirror is ON when the
rear window defogger is ON (Fig. 1).

DIAGNOSIS AND TESTING - HEATED MIRROR
TEST

Heated mirrors are available on models with

Power Mirrors and Rear Window Defogger only. The
heated mirror is controlled by the rear window defog-
ger switch. The heated mirror is ON when the rear
window defogger is ON.

(1) The mirror glass should be warm to the touch.
(2) If not, check the 20 amp fuse (11) in the Power

Distribution Center (PDC) part of the Integrated
Power Module (IPM) in the engine compartment.

(3) Test voltage at rear window defogger switch.
• If no voltage repair wire.

• Remove mirror glass and test the wires for con-

tinuity. If no continuity repair wires.

• If wires are OK, test and replace mirror assem-

bly.

• To test defogger switch refer to the appropriate

section in Electrical.

MIRROR SWITCH

DESCRIPTION

The heated mirror switch is integrated into the

rear window defogger switch located in the HVAC
control panel (Fig. 1).

OPERATION

A LED indicator will illuminate when the switch is

activated. The switch energizes the HVAC control
assembly when it requests the Front Control Module
(FCM) to activate the rear window defogger relay.
The relay controls the current to flow to the grids of
the rear window defogger and the heated power side
view mirrors. The defogger relay will be on for
approximately 10 minutes or until the control switch
or ignition is turned off.

Fig. 1 HVAC CONTROL PANEL

1 - TRIM BEZEL
2 - ACT SENSOR
3 - A/C REQUEST SWITCH
4 - REAR WINDOW DEFOGGER/HEATED MIRRORS SWITCH
COMBO
5 - FRONT WINDOW DEFROSTER MODE SELECTOR

HEATED MIRRORS

8G - 5

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