Chrysler Pacifica. Manual — part 493

(4) If the system operation has been verified but

defogger switch LED indicator does not illuminate,
replace the A/C-heater control.

(5) If broken defogger grid lines are suspected, use

a 12-volt DC voltmeter and contact terminal B with
the negative lead and each rear glass heating grid
line at it’s mid-point with the positive lead. The volt-
meter should read approximately 6 volts at each grid
line mid-point C. If the voltmeter does not read
approximately 6 volts, repair the open grid line(s)
(Refer to 8 - ELECTRICAL/HEATED GLASS/REAR
WINDOW DEFOGGER GRID - STANDARD PROCE-
DURE).

REAR WINDOW DEFOGGER
RELAY

DESCRIPTION

The rear window defogger (EBL) relay (Fig. 4) is a

International

Standards

Organization

(ISO)-type

relay. Relays conforming to the ISO specifications
have common physical dimensions, current capaci-
ties, terminal functions and patterns. The EBL relay
is a electromechanical device that switches battery
current through a fuse in the integrated power mod-
ule (IPM) to the rear window defogger grid, the light-
emitting diode (LED) indicator of the defogger switch
and to the outside mirror heating grids (when
equipped with heated mirrors). The EBL relay is
energized when the relay coil is provided a ground
path by the control circuitry within the IPM.

The rear window defogger relay is located in the

IPM in the engine compartment.

OPERATION

The ISO-standard rear window defogger (EBL)

relay is an electromechanical switch that uses a low
current input controlled by the integrated power
module (IPM) to control the high current output to
the rear window defogger grid lines The movable,
common feed relay contact is held against the fixed,
normally closed relay contact by spring pressure.
When the electromagnetic relay coil is energized, it
draws the movable common feed relay contact away
from the fixed, normally closed relay contact and,
holds it against the fixed, normally open relay con-
tact. This action allows high current to flow to the
rear window defogger grid lines.

When the relay coil is de-energized, spring pres-

sure returns the movable relay contact back against
the fixed, normally closed contact point. The resistor
or diode is connected in parallel with the relay coil,
and helps to dissipate voltage spikes and electromag-
netic interference that can be generated as the elec-
tromagnetic field of the relay coil collapses.

The EBL relay cannot be repaired and, if faulty or

damaged, it must be replaced. Refer to the appropri-
ate wiring information for diagnosis and testing of
the ISO-standard relay and for complete rear window
defogger (EBL) wiring diagrams.

REMOVAL

(1) Disconnect and isolate the negative battery

cable.

(2) Remove the cover from the integrated power

module (IPM) (Fig. 5) located in the engine compart-
ment.

Fig. 3 Grid Line Test

1 - VOLTMETER
2 - VOLTAGE FEED (A)
3 - FEED WIRE
4 - MID-POINT (C)
5 - HEATED WINDOW GRID
6 - GROUND WIRE
7 - GROUND (B)

Fig. 4 Rear Window Defogger (EBL) Relay

30

COMMON FEED

85

COIL BATTERY

86

COIL GROUND

87

NORMALLY OPEN

87A

NORMALLY CLOSED

CS

HEATED GLASS

8G - 3

HEATED GLASS (Continued)

NOTE: Refer to the fuse and relay layout map on
the inside of the IPM cover for EBL relay location.

(3) Remove the EBL relay from the IPM.

INSTALLATION

NOTE: Refer to the fuse and relay layout map on
the inside of the IPM cover for EBL relay location.

(1) Position the EBL relay into the proper recepta-

cle of the integrated power module (IPM).

(2) Align the EBL relay terminals with the termi-

nal cavities in the IPM receptacle and push down
firmly on the relay until the terminals are fully
seated.

(3) Install the cover onto the IPM.
(4) Reconnect the negative battery cable.

REAR WINDOW DEFOGGER
SWITCH

DESCRIPTION

The switch for the rear window defogger (EBL)

system is integrated into the A/C-heater control,
which is located in the center of the instrument
panel (Fig. 6). When the rear window defogger switch
is activated, the A/C-heater control requests the inte-
grated power module (IPM) to operate the rear win-
dow defogger (EBL) relay.

When the EBL relay is activated, current is

directed to the rear defogger grid lines and the
heated side view mirrors (if equipped). The grid lines
heat the glass to help clear the surface of fog or frost.

OPERATION

An LED indicator will illuminate when the rear

window defogger switch is activated. When the
switch is activated, the A/C-heater control requests
the integrated power module (IPM) to operate the
rear window defogger (EBL) relay. The EBL relay
controls the current flow to the grids of the rear win-
dow defogger and to the heated side view mirrors,
when equipped.

NOTE: The EBL system turns off automatically after
10 minutes of initial operation. Each following acti-
vation cycle of the EBL system will last five min-
utes.

The EBL system will initially be on for approxi-

mately ten minutes or until the rear window defog-
ger switch or the ignition switch is turned off. After
the initial time interval has expired, if the defogger
switch is turned On again during the same ignition
cycle, the EBL system will automatically turn off
after about five minutes.

The rear window defogger switch and the rear win-

dow defogger LED indicator cannot be repaired and,
if faulty or damaged, the A/C-heater control must be
replaced (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - FRONT/A/C HEATER CON-
TROL - REMOVAL).

Fig. 5 Integrated Power Module

1 - BATTERY
2 - INTEGRATED POWER MODULE (IPM)
3 - BATTERY THERMAL GUARD

Fig. 6 Rear Window Defogger Switch

1 - A/C-HEATER CONTROL
2 - REAR WINDOW DEFOGGER (EBL) SWITCH

8G - 4

HEATED GLASS

CS

REAR WINDOW DEFOGGER RELAY (Continued)

REAR WINDOW DEFOGGER
GRID

STANDARD PROCEDURE

GRID LINE AND TERMINAL REPAIR

WARNING: Materials contained in the Repair Kit
(Part Number 04549275) may cause skin or eye irri-
tation. The kit contains epoxy resin and amine type
hardener, which are harmful if swallowed. Avoid
contact with the skin and eyes. For skin contact,
wash the affected areas with soap and water. For
contact with the eyes, flush with plenty of water. Do
not take internally. If taken internally, induce vomit-
ing and call a physician immediately. Use with ade-
quate ventilation. Do not use near fire or flame.
Contains flammable solvents. Keep out of the reach
of children. Failure to follow the warnings could
result in possible personal injury or death.

Repair of the rear glass heating grid lines, bus

bars or terminals can be accomplished using the
Mopar

t Rear Window Defogger Repair Kit (Part

Number 04549275) or equivalent.

(1) Mask the repair area with masking tape so

that the conductive epoxy can be applied neatly (Fig.
7). Extend the epoxy application onto the grid line or
the bus bar on each side of the break.

(2) Follow the instructions in the repair kit for

preparing the damaged area.

(3) Remove the package separator clamp and mix

the two conductive epoxy components thoroughly
within the packaging. Fold the package in half and
cut the center corner to dispense the epoxy.

(4) For grid line repairs, mask the area to be

repaired with masking tape or use a template.

(5) Apply the epoxy through the slit in the mask-

ing tape or template. Overlap both ends of the break
by at least 19 millimeters (0.75 inch).

(6) For a terminal replacement, mask the adjacent

areas so the epoxy can be extended onto the adjacent
grid line as well as the bus bar. Apply a thin layer of
epoxy to the area where the terminal was fastened
and onto the adjacent grid line.

(7) Apply a thin layer of conductive epoxy to the

terminal and place it in the proper location on the
bus bar. To prevent the terminal from moving while
the epoxy is curing, it must be wedged or clamped.

(8) Carefully remove the masking tape or tem-

plate.

CAUTION: Do not allow the glass surface to exceed
204° C (400° F) when using a heat gun, or the glass
may fracture.

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

perature, or carefully use a heat gun for fifteen min-
utes. When using a heat gun, hold it approximately
25.4 centimeters (10 inches) from the repair and do
not allow the glass surface to exceed 204° C (400° F).

NOTE: Do not attach the wire harness connectors
to the terminals until the curing process is com-
plete.

(10) After the conductive epoxy is properly cured,

remove the wedge or clamp from the terminal.

(11) Connect the wire harness leads to the grid

terminals and verify EBL operation.

Fig. 7 Grid Line Repair

1 - BREAK
2 - GRID LINE
3 - MASKING TAPE

CS

HEATED GLASS

8G - 5

HEATED MIRRORS

TABLE OF CONTENTS

page

page

HEATED MIRRORS

DESCRIPTION

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

OPERATION

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

HEATED MIRRORS

DESCRIPTION

The optional heated mirror system is controlled by

the momentary rear window defogger switch which is
integral to the A/C-heater control (Fig. 1). An amber
indicator lamp in the switch will illuminate to indi-
cate when the rear window defogger (EBL) system is
turned on.

The heated mirror system only operates in concert

with the EBL system, and will be automatically shut
off after a programmed time interval of about 10
minutes. After the initial time interval has expired, if
the defogger switch is turned on again during the
same ignition cycle, the heated mirror system will
automatically shut off after about 5 minutes.

The heated mirror system will automatically shut

off if the ignition switch is turned to the Off position,
or it can be shut off manually by pressing the rear
window defogger switch a second time.

OPERATION

When the rear window defogger switch is pressed,

the rear window defogger (EBL) system becomes acti-
vated and an electric heater grid located behind the
glass of each of the outside rear view mirrors is ener-
gized. When energized, each of these heater grids
produce heat to help clear the outside rear view mir-
rors of ice, snow, or fog.

If the outside mirror heating grids are both inoper-

ative, refer to 8 - ELECTRICAL/HEATED GLASS -
DIAGNOSIS AND TESTING in this group. If only
one of the outside mirror heating grids is inoperative,
refer to 8 - ELECTRICAL/POWER MIRRORS -
DIAGNOSIS AND TESTING.

The heating grid behind each outside mirror glass

cannot be repaired and, if faulty or damaged, the
entire power mirror assembly must be replaced.

Fig. 1 Rear Window Defogger Switch

1 - A/C-HEATER CONTROL
2 - REAR WINDOW DEFOGGER (EBL) SWITCH

8G - 6

HEATED MIRRORS

CS