CAUTION: Grid lines can be damaged or scraped off with sharp instruments. Care should be taken in clean-
ing glass or removing foreign materials, decals or stickers. Normal glass cleaning solvents or hot water
used with rags or toweling is recommended.

The rear window defogger system, also known as
electric backlight (EBL), consists of two vertical bus
bars (1) linked by a series of grid lines (2) fired onto
the inside surface of the rear window (3).

The EBL system is turned On or Off by a switch in the
A/C-heater control located at the center of the instru-
ment panel and by a timing circuit integral to the front
control module (FCM).

Circuit protection is provided by two cartridge fuses
located in the integrated power module (IPM) in the
engine compartment. One fuse is for the control circuit
and the other fuse is for the heated grid circuit.

HEATED GLASS - SERVICE INFORMATION

8G - 11

OPERATION

The electric backlight (EBL) system is controlled by a
momentary switch (1) located in the A/C-heater control
(2) on the instrument panel. When the rear window
defogger switch is pressed to the On position, the
front control module (FCM) energizes the rear window
defogger (EBL) relay, which then directs fused battery
current through the relay and to the rear defogger grid
lines

and

the

heated

side

view

mirrors,

when

equipped. The grid lines heat the glass to help clear
the rear window and side mirror surfaces of fog or
frost.

An amber indicator (3) in the rear window defogger
switch will illuminate to indicate when the EBL system
is turned on. The FCM contains the EBL system con-
trol circuitry including the timer logic.

NOTE: The EBL system turns off automatically
after approximately ten minutes of initial opera-
tion. Each following activation cycle of the EBL
system will last approximately five minutes.

The EBL system will be automatically turned off after an initial programmed time interval of about ten minutes. After
the initial time interval has expired, if the rear window defogger switch is turned on again during the same ignition
cycle, the EBL system will automatically turn off after about five minutes. The EBL system will automatically shut off
if the ignition switch is turned to the Off position, or it can be turned off manually by pressing the rear window
defogger switch a second time.

Repair of the rear defogger grid lines, bus bars, terminals or pigtail wires can be accomplished using the Mopar
Rear Window Defogger Repair Kit (Part Number 04549275) or equivalent (Refer to 8 - ELECTRICAL/HEATED
GLASS/REAR WINDOW DEFOGGER GRID - STANDARD PROCEDURE - GRID LINE AND TERMINAL REPAIR).

DIAGNOSIS AND TESTING

ELECTRIC BACKLIGHT (EBL) SYSTEM

NOTE: Illumination of the defogger switch indicator lamp does not necessary mean that electrical current is
reaching the rear glass heating grid lines.

NOTE: For circuit descriptions and diagrams of the rear window defogger system, refer to 8W - WIRING
DIAGRAM INFORMATION.

Operation of the electrical backlight (EBL) system can be confirmed by the following:

8G - 12

HEATED GLASS - SERVICE INFORMATION

1. Using a scan tool, check for diagnostic trouble

codes (DTCs) related to the A/C-heater control and
the front control module (FCM) (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - HVAC SELF DIAGNOSTICS). If
no DTCs are found, go to Step 2. If any DTCs are
found, repair as required, then proceed to Step 2

2. Turn the ignition switch to the On position. Set the

rear window defogger switch in the On position.
The rear window defogger operation can be
checked by feeling the rear window glass or the
heated outside rear view mirror glass. A distinct dif-
ference in temperature between the grid lines (4
and 5) and the adjacent clear glass or the mirror
glass should be detected within three to four min-
utes of operation.

3. If a temperature difference is not detected, use a 12-volt DC voltmeter and contact the rear glass heating grid

terminal A (1) with the negative lead, and terminal B (2) with the positive lead. The voltmeter should read battery
voltage. If the voltmeter does not read battery voltage, check the following:

•

Confirm that the ignition switch is in the On position.

•

Make sure that the rear glass heating grid feed wire (3) and ground wire (6) are connected to the terminals.
Confirm that the ground wire has continuity to ground.

•

Check the EBL relay and fuses located in the integrated power module (IPM) in the engine compartment. The
relay and fuses must be tight in their receptacles and all electrical connections must be secure. Refer to the
appropriate wiring information for diagnosis and testing of the ISO-standard relay.

When the above steps have been completed and the rear glass heating grid is still inoperative, one or more of the
following is faulty:

•

Rear window defogger switch in the A/C-heater control.

•

Rear window defogger grid lines (all grid lines would have to be broken, or the power feed or the ground wire
disconnected, for the entire heating grid to be inoperative).

4. If the EBL system operation has been verified but the rear window defogger LED indicator does not illuminate,

replace the A/C-heater control (Refer to 24 - HEATING & AIR CONDITIONING/CONTROLS/CONTROL-A/C
HEATER - REMOVAL).

GRID-REAR WINDOW DEFOGGER

STANDARD PROCEDURE

GRID LINE AND TERMINAL REPAIR

WARNING: Materials contained in the Repair Kit (Part Number 04549275) may cause skin or eye irritation.
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 vomiting and call a physician
immediately. Use with adequate 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, terminals or pigtail wires can be accomplished using the Mopar
Rear Window Defogger Repair Kit (Part Number 04549275) or equivalent.

HEATED GLASS - SERVICE INFORMATION

8G - 13

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