HEATED SYSTEMS
TABLE OF CONTENTS
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HEATED GLASS........................... 1
HEATED MIRRORS......................... 5HEATED SEAT SYSTEM..................... 7
HEATED GLASS
TABLE OF CONTENTS
page page
HEATED GLASS
DESCRIPTION............................1
OPERATION.............................2
DEFOGGER RELAY
DESCRIPTION............................2
REAR WINDOW DEFOGGER GRID
STANDARD PROCEDURE...................2
GRID LINE REPAIR-REAR.................2REAR WINDOW DEFOGGER SWITCH
DESCRIPTION............................2
OPERATION.............................2
WINDSHIELD GRID
DIAGNOSIS AND TESTING..................3
SYSTEM TEST..........................3
STANDARD PROCEDURE...................3
GRID LINE AND TERMINAL REPAIR.........3
HEATED GLASS
DESCRIPTION
The electrically heated Rear Window Defogger (Fig.
1), Heated Power Side View Mirrors, and HeatedWindshield Wiper De-icer (Fig. 2) is available on
select models.
Fig. 1 REAR WINDOW DEFOGGER (TYPICAL)
1 - REAR DEFOGGER GRID
2 - REAR WINDOW
Fig. 2 (TYPICAL) Heated Windshield Wiper De-icer
1 - DEFROSTER OUTLET
2 - VIN #
3 - HEATED WINDSHIELD GRID
RSHEATED SYSTEMS8G-1
OPERATION
The Rear Window Defogger (Fig. 1) system consists
of two vertical bus bars linked by a series of grid
lines on the inside surface of the rear window. The
electrical circuit consists of the rear defogger 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 integrated as a unit call Integrated Power Module
(IPM). The rear defogger switch and relay also acti-
vates the heated power side view mirrors and heated
windshield wiper de-icer. The heated windshield
wiper de-icer 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-servi-
cable 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
relay/timer is bypassed, the heated windshield wiper
de-icer will stay ON until the another mode is
selected. For circuit information and component loca-
tion refer to appropriate section for Wiring Diagrams.
CAUTION:
Since grid lines can be damaged or scraped off
with 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 recom-
mended.
DEFOGGER RELAY
DESCRIPTION
There is no heated glass relay it is integrated into
the (E.B.L) relay that is located in the IPM in the
engine compartment.
REAR WINDOW DEFOGGER
GRID
STANDARD PROCEDURE - GRID LINE
REPAIR-REAR
For Grid repair procedure for the rear window
defogger (Refer to 8 - 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 and the heated windshield wiper de-icer. The
defogger relay will be on for approximately 10 min-
utes or until the control switch or ignition 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 GLASSRS
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:
²Confirm that ignition switch is ON.
²Ensure 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.
²Ensure 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:
²HVAC control assembly
²Rear window defogger relay in the IPM.
²Check for loose connector or a wire pushed out
of connector.
²Rear 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 HARD-
ENER, HARMFUL IF SWALLOWED. AVOID CON-
TACT WITH SKIN AND EYES. FOR SKIN, WASH
AFFECTED AREAS WITH SOAP AND WATER. DO
NOT TAKE INTERNALLY. IF TAKEN INTERNALLY,
INDUCE VOMITING; CALL A PHYSICIAN IMMEDI-
ATELY. IF IN CONTACT WITH EYES, FLUSH WITH
PLENTY OF WATER. USE WITH ADEQUATE VENTI-
LATION. DO NOT USE NEAR FIRE OR FLAME. CON-
TENTS CONTAINS 3% FLAMMABLE SOLVENTS.
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 MopartRepair 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.
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
RSHEATED GLASS8G-3
HEATED MIRRORS
TABLE OF CONTENTS
page page
HEATED MIRRORS
DESCRIPTION............................5
OPERATION.............................5
DIAGNOSIS AND TESTING..................5
HEATED MIRROR TEST...................5
MIRROR SWITCH
DESCRIPTION............................5OPERATION.............................5
HEATED MIRROR GRID
STANDARD PROCEDURE...................6
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 TESING - 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.
²If no voltage repair wire.
²Remove mirror glass and test the wires for con-
tinuity. If no continuity repair wires.
²If wires are OK, replace mirror glass.
²To 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, heated power side view
mirrors and the heated windshield wiper de-icer. The
defogger relay will be on for approximately 10 min-
utes 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
RSHEATED MIRRORS8G-5
HEATED MIRROR GRID
STANDARD PROCEDURE - HEATED MIRROR
Replacement of the mirror is necessary if the grid
is damaged and diagnostics have been performed
(Refer to 23 - BODY/EXTERIOR/SIDE VIEW MIR-
ROR - REMOVAL).
RELAY
DESCRIPTION
There is no heated mirror relay it is integrated
into the (E.B.L) relay that is located in the IPM in
the engine compartment.
8G - 6 HEATED MIRRORSRS
²Remote Keyless Entry Module (RKE)- Refer
toRemote Keyless Entry Modulein Power Locks
for more information.
²Electronic Vehicle Information Center
(EVIC)- Refer toElectronic Vehicle Information
Centerin Overhead Console for more information.
²Heated Seat Module (HSM)- Refer toHeated
Seat Modulein Electronic Control Modules for more
information.
²Memory Heated Seat Module (MHSM)-If
the vehicle is equipped with the Memory System,
refer toMemory Seat Mirror Module (MSMM)in
Electronic Control Modules for more information.
Refer toWiring Diagramsfor complete circuit
diagrams. Following are general descriptions of the
major components in the heated seat system.
OPERATION
The heated seat system will only operate when the
ignition switch is in the On position, and the surface
temperature at the front seat heating element sen-
sors is below the designed temperature set points of
the system. The heated seat system will not operate
in ambient temperatures greater than about 41É C
(105É F). The front seat heating elements and sensors
are hard wired to the Heated Seat Module (HSM) or
the Memory Heated Seat Module (MHSM).
The heated seat switches are hard wired to the
Body Control Module (BCM). The BCM monitors the
heated seat switch inputs, then sends heated seat
switch status messages to the HSM or MHSM over
the Programmable Communications Interface J1850
(PCI) data bus. The HSM or MHSM contains the con-
trol logic for the heated seat system. The HSM or
MHSM responds to the heated seat switch status
messages, ignition switch status messages, and the
front seat heating element sensor inputs by control-
ling the output to the front seat heating elements
through integral solid-state relays.
When a seat heater is turned on, the sensor
located on the seat cushion electric heater element
provides the HSM or MHSM with an input indicating
the surface temperature of the seat cushion. If the
surface temperature input is below the temperature
set point for the selected Low or High heated seat
switch position, the HSM or MHSM energizes the
integral solid-state relay, which supplies battery cur-
rent to the heating elements in the seat cushion and
back. When the sensor input indicates the correct
temperature set point has been achieved, the HSM or
MHSM de-energizes the solid-state relay. The HSM
or MHSM will continue to cycle the solid-state relay
as needed to maintain the temperature set point.
The HSM or MHSM and the seat heater elements
operate on non-switched battery current supplied
through the power seat fuse in the intelligent powermodule. However, the HSM or MHSM will automati-
cally turn off the heating elements if it detects an
open in the sensor circuit, a short in the heating ele-
ment circuit causing an excessive current draw, or
when the ignition switch is turned to the Off posi-
tion.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the heated seat system.
DRIVER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are mounted in the
instrument panel center bezel (Fig. 2). The two three-
position rocker-type switches, one switch for each
front seat, are incorporated into one large switch
assembly that also includes the hazzard, rear window
wiper and washer switches. The heated seat switches
provide a resistor multiplexed signal to the Body
Control Module (BCM) through separate hard wired
circuits. Each switch has an Off, Low, and High posi-
tion so that both the driver and the front seat pas-
senger can select a preferred seat heating mode.
Each switch has two Light-Emitting Diodes (LED)
which light to indicate that the heater for the seat is
turned on.
The heated seat switches and their LEDs cannot
be repaired. If either switch or LED is faulty or dam-
aged, the entire switch assembly must be replaced.
Fig. 2 HEATED SEAT SWITCHES
8G - 8 HEATED SEAT SYSTEMRS
HEATED SEAT SYSTEM (Continued)
HORN
TABLE OF CONTENTS
page page
HORN
DESCRIPTION............................1
OPERATION.............................1
DIAGNOSIS AND TESTING..................1
HORN
DIAGNOSIS AND TESTING..................3
REMOVAL...............................4INSTALLATION............................5
HORN RELAY
DIAGNOSIS AND TESTING..................5
REMOVAL...............................5
INSTALLATION............................5
HORN SWITCH
DESCRIPTION............................5
HORN
DESCRIPTION
HORN SYSTEM
WARNING:
ON VEHICLES EQUIPPED WITH AIRBAG, REFER TO
ELECTRICAL, RESTRAINTS FOR SAFETY PRECAU-
TIONS. DISCONNECT THE NEGATIVE CABLE FROM
THE BATTERY BEFORE SERVICING COMPONENTS
INVOLVING THE AIRBAG SYSTEM. ACCIDENTAL
DEPLOYMENT OF AIRBAG AND PERSONAL INJURY
CAN RESULT.
The horn circuit consists of a horn switch, clock-
spring, horn relay, horns and intelligent power mod-
ule. The horn switch is a membrane switch located in
the airbag trim cover. The horns are located forward
of the left front wheel behind the bumper fascia.
OPERATION
The horn relay plugs into the intelligent power
module which is located in the engine compartment.
For circuit information and component locations,
refer to the appropriate wiring information. The wir-
ing information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
The horns will not function if the switch is
ªCLOSEDº for more than 30 seconds. Once the
switch is ªOPENº, a 20±30 second delay will occur
before the horns are functional again.
DIAGNOSIS AND TESTING
Refer to Horn System Test below. If the horn does
not sound, check horn fuse located in the intelligent
power module. If the fuse is blown, replace with the
correct fuse. If the horns fail to sound and the new
fuse blows when depressing the horn switch, a short
circuit in the horn or the horn wiring between the
fuse terminal and the horn is responsible, or a defec-
tive horn switch allowed the horn to burn out is
responsible.
If the fuse is OK, test horn relay (Refer to 8 -
ELECTRICAL/HORN/HORN RELAY - DIAGNOSIS
AND TESTING).
If the relay is OK, test horn. Refer to Horn System
Test.
CAUTION:
Continuous sounding of horn may cause horn relay
to fail.
Should the horn sound continuously:
²Unplug the horn relay from intelligent power
module.
²Refer to (Refer to 8 - ELECTRICAL/HORN/
HORN RELAY - DIAGNOSIS AND TESTING).
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
RSHORN8H-1
HORN SYSTEM TEST
CONDITION POSSIBLE CAUSE CORRECTION
HORN SOUNDS CONTINUOUSLY.
NOTE: IMMEDIATELY UNPLUG
HORN RELAY IN THE
INTELLIGENT POWER MODULE.(1) FAULTY HORN RELAY. (1) REFER TO HORN RELAY
TEST.
(2) HORN CONTROL CIRCUIT TO
RELAY SHORTED TO GROUND.(2) CHECK TERMINAL 85 IN
INTELLIGENT POWER MODULE
FOR CONTINUITY TO GROUND.
IF CONTINUITY TO GROUND
INDICATES:
(A) STEERING WHEEL HORN
SWITCH/LEAD SHORTED TO
GROUND.
(B) WIRING HARNESS SHORTED
TO GROUND. FIND THE SHORT
AND REPAIR AS NECESSARY.
(3) PINCHED HORN SWITCH
WIRE UNDER DRIVER AIRBAG
MODULE.(3) REPLACE DRIVER AIRBAG
MODULE TRIM.
(4) FAULTY HORN SWITCH. (4) REPLACE DRIVER AIRBAG
MODULE TRIM.
(5) FAULTY CLOCKSPRING. (5) REPLACE CLOCKSPRING.
HORN SOUND INTERMITTENTLY
AS THE STEERING WHEEL IS
TURNED.(1) HORN RELAY CONTROL
CIRCUIT X3 IS SHORTED TO
GROUND INSIDE STEERING
COLUMN OR WHEEL.(1) REMOVE DRIVER AIRBAG
MODULE AND/OR WHEEL.
CHECK FOR RUBBING OR
LOOSE WIRE/CONNECTOR,
REPAIR AS NECESSARY.
(2) PINCHED HORN SWITCH
WIRE UNDER DRIVER AIRBAG
MODULE.(2) REPLACE DRIVER AIRBAG
MODULE TRIM.
(3) FAULTY HORN SWITCH. (3) REPLACE DRIVER AIRBAG
MODULE TRIM.
(4) FAULTY CLOCKSPRING. (4) REPLACE CLOCKSPRING.
HORN DOES NOT SOUND (1) CHECK FUSE 8 IN
INTELLIGENT POWER MODULE.(1) REPLACE FUSE IF BLOWN
REPAIR AS NECESSARY.
(2) NO VOLTAGE AT HORN
RELAY TERMINALS 30 & 86, AND
FUSE IS OK.(2) NO VOLTAGE, REPAIR THE
CIRCUIT AS NECESSARY.
(3) OPEN CIRCUIT FROM
TERMINAL 85 OF THE HORN
RELAY TO HORN SWITCH, X3
CIRCUIT.(3) REPAIR CIRCUIT AS
NECESSARY.
(4) FAULTY OR DAMAGED HORN. (4) VOLTAGE AT HORN WHEN
HORN SWITCH IS PRESSED,
REPLACE HORN.
(5) FAULTY HORN SWITCH. (5) REPLACE DRIVER AIRBAG
MODULE TRIM.
(6) FAULTY CLOCKSPRING. (6) REPLACE CLOCKSPRING.
8H - 2 HORNRS
HORN (Continued)