wiring diagram JEEP LIBERTY 2002 KJ / 1.G Owner's Manual

REAR WINDOW DEFOGGER
SWITCH
DESCRIPTION
The rear window defogger switch is installed in the
instrument panel HVAC contol head assembly. The
momentary-type switch provides a hard-wired ground
signal to the HVAC control head each time it is
depressed. The instrument cluster rear window
defogger timer and logic circuitry responds by ener-
gizing or de-energizing the rear window defogger
relay.
OPERATION
Energizing the rear window defogger relay pro-
vides electrical current to the rear window defogger
grid and, if the vehicle is so equipped, the outside
rear view mirror heating grids. An amber indicator
lamp in the defogger switch, which lights to indicate
when the defogger system is turned On, is also pow-
ered by the defogger relay output.
The defogger switch illumination lamp and indica-
tor lamp bulbs are serviceable. The defogger switch
cannot be repaired and, if faulty or damaged the
entire HVAC control head assembly must be
replaced.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER SWITCH
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Remove the HVAC control head assembly from
the instrument panel and unplug the defogger switch
wire harness connector-B.
(2) Check for continuity between the ground cir-
cuit cavity of the defogger switch wire harness con-nector and a good ground. There should be
continuity. If OK, go to Step 3. If not OK, repair the
open circuit as required.
(3) Check for continuity between the ground cir-
cuit terminal and the rear window defogger switch
sense circuit terminal on the back of the defogger
switch housing (Fig. 5). There should be momentary
continuity as the defogger switch button is depressed,
and then no continuity. If OK, (Refer to 8 - ELEC-
TRICAL/HEATED GLASS/REAR WINDOW DEFOG-
GER SWITCH - DIAGNOSIS AND TESTING -
INSTRUMENT CLUSTER REAR WINDOW DEFOG-
GER FUNCTION) If not OK, replace the faulty
switch (Fig. 5).
(4) Check switch position continuity between:
CONTACT PINS
1 - OFF LAMPS A-1 - A-7
2 - ON MOMENTARY B-6 - B-8
3 - ILLUMINATION LAMP A-7 - A-1
4 - INDICATOR LAMP B-12 - B-7
Fig. 5 A/C HEATER CONTROL HEAD (Rear View)
1 - A/C HEATER CONTROL HEAD
2 - A/C HEATER CONTROL HEAD LIGHT
3 - REAR WINDOW DEFOGGER SWITCH AND TEMPERATURE
BLEND DOOR- CONNECTOR B (12 PIN)
4 - A/C HEATER CONTROL HEAD LIGHT
5 - MODE SELECT CONTROL
6 - BLOWER SPEED CONTROL- CONNECTOR A (7 PIN)
7 - MOUNTING SCREWS (4)
8G - 8 WINDOW DEFOGGERKJ

DIAGNOSIS AND TESTING - REAR HVAC
CONTROL ASSEMBLY WINDOW DEFOGGER
FUNCTION
Before performing this test, complete the Defogger
Switch and Defogger Relay tests as described in this
group. For circuit descriptions and diagrams, (Refer
to Appropriate Wiring Information).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Remove the defogger relay from the junction
block and unplug the defogger switch wire harness
connector.
(2) Remove the HVAC control head from the
instrument panel. This is accomplished by removing
the ashtray and the screw behind the ashtray and
uncliping the center bezel.
(3) Check for continuity between the rear window
defogger switch sense circuit cavity of the cluster
wire harness connector (connector B) and a good
ground. There should be no continuity. If OK, go to
Step 4. If not OK, repair the short circuit as
required.
(4) Check for continuity between the rear window
defogger switch sense circuit cavity of the right
instrument cluster wire harness connector (connector
B) and the defogger switch wire harness connector.
There should be continuity. If OK, go to Step 5. If not
OK, repair the open circuit as required.
(5) Check for continuity between the rear window
defogger relay control circuit cavity of the right
instrument cluster wire harness connector (connectorB) and a good ground. There should be no continuity.
If OK, go to Step 6. If not OK, repair the short circuit
as required.
(6) Check for continuity between the rear window
defogger relay control circuit cavities of the right
instrument cluster wire harness connector (connector
B) and the defogger relay receptacle (the cavity for
ISO relay terminal 85) in the junction block. There
should be continuity. If OK, replace the faulty HVAC
control head. If not OK, repair the open circuit as
required.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) The Rear Window Defogger switch is part of
the HVAC assembly and if damaged or inoperative
the entire HVAC control assembly must be replace-
d(Refer to 24 - HEATING & AIR CONDITIONING/
CONTROLS/A/C HEATER CONTROL - REMOVAL).
INSTALLATION
(1) The Rear Window Defogger switch is part of
the HVAC control assembly and if damaged or inop-
erative you must replace the entire HVEAC control
head assembly(Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/A/C HEATER CONTROL -
INSTALLATION).
(2) Connect the battery negative cable.
KJWINDOW DEFOGGER 8G - 9
REAR WINDOW DEFOGGER SWITCH (Continued)

HEATED SEAT SYSTEM
TABLE OF CONTENTS
page page
HEATED SEAT SYSTEM
DESCRIPTION.........................10
OPERATION...........................10
DIAGNOSIS AND TESTING - HEATED SEAT
SYSTEM............................11
DRIVER SEAT HEATER SWITCH
DESCRIPTION.........................11
OPERATION...........................12
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH............................12
REMOVAL.............................13
INSTALLATION.........................13
HEATED SEAT ELEMENT
DESCRIPTION.........................13OPERATION...........................13
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT...........................13
HEATED SEAT SENSOR
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR............................14
PASSENGER SEAT HEATER SWITCH
DESCRIPTION.........................14
OPERATION...........................14
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH............................14
REMOVAL.............................15
INSTALLATION.........................15
HEATED SEAT SYSTEM
DESCRIPTION
Individually controlled electrically heated front
seats are available on models that are also equipped
with the optional leather trim package. Vehicles with
this option can be visually identified by the two sep-
arate heated seat switches mounted on the outboard
seat cushion side shields. The heated seat system
allows the front seat driver and passenger to select
from two different levels of supplemental electrical
seat heating, or no seat heating to suit their individ-
ual comfort requirements. The heated seat system for
this vehicle includes the following major components:
²Heated Seat Switches- Two heated seat
switches are used per vehicle, including two Light-
Emitting Diode (LED) indicator lamps and an incan-
descent back lighting bulb for each switch. One
switch for the driver and one for the passenger front
seats. The switches are mounted on the outboard
seat cushion side shields.
²Heated Seat Module- also referred to as the
Seat Heat Interface Module (SHIM), this module con-
tains the solid state electronic control and diagnostic
logic circuitry for the heated seat system. One heated
seat module is used per vehicle and is mounted
under the left front seat cushion. Refer to the Elec-
tronic Control Modules section of the service manual
for heated seat module information.
²Heated Seat Elements- Four heated seat ele-
ments are used per vehicle, one for each front seat
back and one for each front seat cushion. The ele-
ments are integral to the individual front seat andseat back cushions and cannot be removed from the
cushions, once installed at the factory.
²Heated Seat Sensors- Two heated seat sen-
sors are used per vehicle, one for each front seat. The
sensors are integral to the individual front seat heat-
ing elements.
Following are general descriptions of the major
components in the heated seat system. See the own-
er's manual in the vehicle glove box for more infor-
mation on the features, use and operation of the
heated seat system. Refer toWiring Diagramsfor
the location of complete heated seat system wiring
diagrams.
OPERATION
The heated seat module receives fused battery cur-
rent through fuse #29 in the Junction Block (JB)
when the ignition switch is in the ªONº position. The
heated seat switches receive battery current through
fuse #25 in the Junction Block also, when the igni-
tion switch is in the ªONº position. The heated seat
module shares a common ground circuit with each of
the heated seat elements. The heated seat elements
will only operate when the surface temperature of
the seat cushion is below the designed temperature
set points of the system.
The heated seat system will also be turned off
automatically whenever the ignition switch is turned
to any position except On. If the ignition switch is
turned to the Off position while a heated seat is
turned ON, the heated seat will remain Off after the
ignition switch is turned back ªONº until a heated
seat switch is depressed again.
8G - 10 HEATED SEAT SYSTEMKJ

The heated seat module monitors inputs from the
heated seat sensors and the heated seat switches. In
response to these inputs the heated seat module uses
its internal programming to control outputs to the
heated seat elements in both front seats and to con-
trol the heated seat LED indicator lamps located in
both of the heated seat switches. The heated seat
module is also programmed to provide self-diagnostic
capability. When the module detects certain failures
within the heated seat system, it will provide a
visual indication of the failure by flashing the indica-
tor lamps in the affected heated seat switch. The
heated seat module will automatically turn off the
heated seat elements if it detects a short or open in
the heated seat element circuit or a heated seat sen-
sor value that is out of range.
DIAGNOSIS AND TESTING - HEATED SEAT
SYSTEM
HEATED SEAT SYSTEM SELF-DIAGNOSIS
The heated seat system is capable of performing
some self-diagnostics. The following table depicts the
various monitored failures which will be reported to
the vehicle operator or technician by flashing the
individual heated seat switch Light Emitting Diode
(LED) indicator lamps. Refer to the Heated Seat Sys-
tem Self-Diagnosis table for failure identification.
The driver side heated seat switch indicator lamps
will flash if a failure occurs in the driver side heated
seat, and the passenger side heated seat switch indi-
cator lamps will flash for a passenger side heated
seat failure. If a monitored heated seat system fail-
ure occurs, the switch indicator lamps will flash at a
pulse rate of about one-half second on, followed by
about one-half second off for a duration of about one
minute after the switch for the faulty heated seat is
depressed in either the Low or High direction. This
process will repeat every time the faulty heated seat
switch is actuated until the problem has been cor-
rected.
Heated Seat System Self-Diagnosis
Monitored FailureSwitch High
Indicator LampSwitch Low
Indicator Lamp
Heated Seat
Element ShortedFlashing Flashing
Heated Seat
Element OpenFlashing Off
Heated Seat
Sensor Value Out
of RangeOff FlashingIf the heated seat system failure is identified by
flashing heated seat switch indicator lamps, go to the
appropriate diagnosis and testing procedure in this
section and confirm the condition, using the step by
step procedure. If the monitored failure is confirmed,
replace the component. If the monitored failure is not
confirmed, replace the heated seat module with a
known good unit and retest the system.
HEATED SEAT SYSTEM TESTING
Refer toWiring Diagramsfor the location of com-
plete heated seat system wiring diagrams. Before
testing the individual components in the heated seat
system, perform the following preliminary checks:
²If a single indicator lamp for one heated seat
switch does not operate and the heated seat elements
do heat, refer toDiagnosis and Testing the
Heated Seat Switchin this section for the location
of heated seat switch diagnosis and testing proce-
dures.
²If both indicator lamps for a heated seat switch
operate, but the heated seat elements do not heat,
refer toDiagnosis and Testing the Heated Seat
Modulein Electronic Control Modules for the loca-
tion of heated seat module diagnosis and testing pro-
cedures.
²If an indicator lamp on either heated seat switch
remains illuminated after the heated seat has been
turned Off, refer toDiagnosis and Testing the
Heated Seat Modulein Electronic Control Modules
for the location of heated seat module diagnosis and
testing procedures. Also refer to the Body Diagnostic
Manual for additional diagnosis and testing proce-
dures.
DRIVER SEAT HEATER
SWITCH
DESCRIPTION
The heated seat switches are located on the out-
board cushion side shield of the driver and passenger
front seats (Fig. 1). The two, three-position rocker
type switches provide a resistor multiplexed signal to
the Heated Seat Module through separate hard wired
circuits. Each switch has an Off, Low and High set-
ting. Each switch contains two light emitting diodes
(LED), one for each High and Low setting to let the
occupant know that the seat heater system is on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
KJHEATED SEAT SYSTEM 8G - 11
HEATED SEAT SYSTEM (Continued)

OPERATION
There are three positions that can be selected with
each of the heated seat switches: Off, Low, and High.
When the front of the switch rocker is fully
depressed, the High position is selected and the high
position LED indicator illuminates. When the rear of
the switch rocker is fully depressed, the Low position
is selected and the low position LED indicator illumi-
nates. When the switch rocker is depressed a second
time in either direction, Off is selected and both LED
indicators are extinguished.
Both switches provide separate resistor multi-
plexed hard wire inputs to the Heated Seat Module
to indicate the selected switch position. The heated
seat module monitors the switch inputs and responds
to the heated seat switch status messages by control-
ling the output to the seat heater elements of the
selected seat. The Low heat position set point is
about 36É C (97É F), and the High heat position set
point is about 41É C (105É F).
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH
If a heated seat fails to heat and one or both of the
indicator lamps on a heated seat switch flash, refer
toHeated Seat System Diagnosis and Testingin
this section for flashing LED failure identification.
Refer toWiring Diagramsfor complete heated seat
system wiring diagrams.
(1) If the problem being diagnosed involves a
heated seat switch indicator lamp that remains illu-
minated after the heated seat has been turned Off,refer toDiagnosis and Testing the Heated Seat
Modulein the Electronic Control Modules section for
heated seat module diagnosis and testing procedures.
If not, go to Step 2
(2) Remove the heated seat switch (Refer to 8 -
ELECTRICAL/HEATED SEATS/DRIVER HEATED
SEAT SWITCH - REMOVAL). Check for continuity
between the ground circuit cavity #5 of the heated
seat switch connector and a good ground. There
should be continuity. If OK, go to Step 3. If not OK,
repair the open ground circuit as required.
(3) Turn the ignition switch to the ON position.
Check for battery voltage at the fused ignition switch
output circuit cavity #1 of the heated seat switch con-
nector. If OK, go to Step 4. If not OK, repair the open
fused ignition switch output circuit as required.
(4) Check the continuity between pin #1 and pin
#3 of the heated seat switch (Fig. 2). If the readings
do not correspond to those in the Heated Seat Switch
Continuity table below, replace the heated seat
switch. If OK, and the heated seat system is still not
operating properly refer toDiagnosis and Testing
the Heated Seat Module.
NOTE: ANY RESISTANCE VALUES (OHMSV) GIVEN
IN THE FOLLOWING TEXT ARE SUPPLIED USING
THE AUTOMATIC RANGE GENERATED BY A
FLUKETAUTOMOTIVE METER. IF ANOTHER TYPE
OF MEASURING DEVICE IS USED, THE VALUES
GENERATED MAY NOT BE THE SAME AS THE
RESULTS SHOWN HERE, OR MAY HAVE TO BE
CONVERTED TO THE RANGE USED HERE.
Fig. 1 KJ POWER / HEATED SEAT
Fig. 2 Heated Seat Switches
8G - 12 HEATED SEAT SYSTEMKJ
DRIVER SEAT HEATER SWITCH (Continued)

HEATED SEAT SENSOR
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
For complete circuit diagrams, refer toWIRING.
NOTE: ANY RESISTANCE VALUES (OHMSV) GIVEN
IN THE FOLLOWING TEXT ARE SUPPLIED USING
THE AUTOMATIC RANGE GENERATED BY A
FLUKETAUTOMOTIVE METER. IF ANOTHER TYPE
OF MEASURING DEVICE IS USED THE VALUES
GENERATED MAY NOT BE THE SAME AS THE
RESULTS SHOWN HERE, OR MAY HAVE TO BE
CONVERTED TO THE RANGE USED HERE.
(1) Disconnect the heated seat wire harness con-
nector from under the seat. Using an ohmmeter,
check the resistance between the heated seat sensor
input circuit cavity and the heated seat sensor feed
circuit cavity in the heated seat wire harness connec-
tor. The heated seat sensor resistance should be
between 1 kilohm and 100 kilohms. If OK, go to Step
2. If not OK, replace the faulty seat heating element
assembly.
(2) Test the seat wire harness between the heated
seat module connector and the heated seat wire har-
ness connector for a shorted or open circuit. If OK,
refer toDiagnosis and Testing the Heated Seat
Modulein Electronic Control Modules, for the
proper heated seat module diagnosis and testing pro-
cedures. If not OK, repair the shorted or open heated
seat wire harness as required.
PASSENGER SEAT HEATER
SWITCH
DESCRIPTION
The heated seat switches are located on the out-
board cushion side shield of the driver and passenger
front seats (Fig. 3). The two, three-position rocker
type switches provide a resistor multiplexed signal to
the Heated Seat Module through separate hard wired
circuits. Each switch has an Off, Low and High set-
ting. Each switch contains two light emitting diodes
(LED), one for each High and Low setting to let the
occupant know that the seat heater system is on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
OPERATION
There are three positions that can be selected with
each of the heated seat switches: Off, Low, and High.
When the front of the switch rocker is fullydepressed, the High position is selected and the high
position LED indicator illuminates. When the rear of
the switch rocker is fully depressed, the Low position
is selected and the low position LED indicator illumi-
nates. When the switch rocker is depressed a second
time in either direction, Off is selected and both LED
indicators are extinguished.
Both switches provide separate resistor multi-
plexed hard wire inputs to the Heated Seat Module
to indicate the selected switch position. The heated
seat module monitors the switch inputs and responds
to the heated seat switch status messages by control-
ling the output to the seat heater elements of the
selected seat. The Low heat position set point is
about 36É C (97É F), and the High heat position set
point is about 41É C (105É F).
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH
If a heated seat fails to heat and one or both of the
indicator lamps on a heated seat switch flash, refer
toHeated Seat System Diagnosis and Testingin
this section for flashing LED failure identification.
Refer toWiring Diagramsfor complete heated seat
system wiring diagrams.
(1) If the problem being diagnosed involves a
heated seat switch indicator lamp that remains illu-
minated after the heated seat has been turned Off,
refer toDiagnosis and Testing the Heated Seat
Modulein the Electronic Control Modules section for
heated seat module diagnosis and testing procedures.
If not, go to Step 2
Fig. 3 KJ POWER / HEATED SEAT
8G - 14 HEATED SEAT SYSTEMKJ

HORN
TABLE OF CONTENTS
page page
HORN SYSTEM
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - HORN SYSTEM . . . 1
HORN
DIAGNOSIS AND TESTING - HORN..........2
REMOVAL.............................3
INSTALLATION..........................3HORN RELAY
DIAGNOSIS AND TESTING - HORN RELAY....3
REMOVAL.............................3
INSTALLATION..........................3
HORN SWITCH
DESCRIPTION..........................4
DIAGNOSIS AND TESTING - HORN SWITCH . . . 4
HORN SYSTEM
DESCRIPTION
A dual-note electric horn system is standard facto-
ry-installed equipment on this model (Fig. 1).
The dual-note horn system features dual electro-
magnetic horn units. The horn system includes the
following major components:
²Horn- The two horns are located below the
Power Distribution Center (PDC).
²Horn Relay- The horn relay is located in the
Junction Block (JB).²Horn Switch- The horn switch is molded into
the driver airbag assembly.OPERATION
The horn system operates on battery current
received through fuse 3 in the Junction Block (JB).
The horn system circuit is designed so that the sys-
tem will remain operational, regardless of the igni-
tion switch position.
DIAGNOSIS AND TESTING - HORN SYSTEM
In most cases, any problem involving continually
sounding horns can be quickly alleviated by removing
the horn relay from the Junction Block (JB). Refer to
horn relay for the removal procedure. Refer to the
appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 1 HORN LOCATION
1 - HIGH NOTE HORN
2 - LOW NOTE HORN
KJHORN 8H - 1

HORN SYSTEM DIAGNOSIS TABLE
CONDITION POSSIBLE CAUSES CORRECTION
BOTH HORNS
INOPERATIVE1. Faulty fuse. 1. Check the fuse in the Junction Block (JB).
Replace the fuse and repair the shorted circuit or
component, if required.
2. Faulty horn relay. 2. Refer to horn relay for the proper diagnosis
and testing procedures. Replace the horn relay or
repair the open horn relay circuit, if required.
3. Faulty horn switch. 3. Refer to horn switch for the proper diagnosis
and testing procedure. Replace the horn switch or
repair the open horn switch circuit, if required.
4. Faulty horns. 4. Refer to horn for the proper diagnosis and
testing procedure. Replace the horns or repair the
open horn circuit, if required.
ONE HORN INOPERATIVE 1. Faulty horn. 1. Refer to horn for the proper diagnosis and
testing procedures. Replace the horn or repair the
open horn circuit, if required.
HORN SOUNDS
CONTINUOUSLY1. Faulty horn relay. 1. Refer to horn relay for the proper diagnosis
and testing procedure. Replace the horn relay or
repair the shorted horn relay control circuit, if
required.
2. Faulty horn switch. 2. Refer to horn switch for the proper diagnosis
and testing procedure. Replace the horn switch or
repair the shorted horn switch circuit, if required.
HORN
DIAGNOSIS AND TESTING - HORN
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, further details
on wire harness routing and retention, as well as
pin-out and location views for the various wire har-
ness connectors, splices and grounds.(1) Disconnect the wire harness connector from the
horn. Measure the resistance between the horn
ground circuit cavity of the wire harness connector
and a good ground. There should be no measurable
resistance. If OK, go to Step 2. If not OK, replace
wiring as necessary.
(2) Check for battery voltage at the horn relay out-
put circuit cavity of the wire harness connector for
the horn. There should be zero volts. If OK, go to
Step 3. If not OK, refer to horn relay and horn relay
circuit for the proper diagnosis and testing proce-
dures.
(3) Depress the horn switch. There should now be
battery voltage at the horn relay output circuit cavity
of the wire harness connector for the horn. If OK, but
the horn does not sound, replace the faulty horn. If
not OK, refer to horn relay and horn relay circuit for
the proper diagnosis and testing procedures.
8H - 2 HORNKJ
HORN SYSTEM (Continued)

REMOVAL
(1)Disconnect and isolate the battery negative cable.
(2) Disconnect the electrical harness connector
from the horns.
(3) Remove the mounting bolt (Fig. 2).
(4) Remove the horns.
INSTALLATION
(1) Install the horns.
(2) Install the mounting bolt. Tighten bolt to 25
N´m (19 lb. ft.).
(3) Connect the electrical harness connector to the
horns
(4) Connect the battery negative cable.
HORN RELAY
DIAGNOSIS AND TESTING - HORN RELAY
(1) Remove horn relay (Refer to 8 - ELECTRICAL/
HORN/HORN RELAY - REMOVAL).
(2) Using ohmmeter, test between relay connector
terminals 85 to 86 for 75   8 ohms resistance. If
resistance not OK, replace relay (Fig. 3).
(3) Test for continuity between ground and termi-
nal 85 of horn relay.
(a) When the horn switch is not depressed, no
continuity should be present.
(b) Continuity to ground when horn switch is
depressed.
(c) If continuity is not correct replace horn
switch or wiring as necessary, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connec-
tor repair procedures, details of wire harness rout-ing and retention, connector pin-out information
and location views for the various wire harness
connectors, splices and grounds.
(4) Using voltmeter, test voltage at:
(a) Terminals 30 and 86 of the horn relay to
body ground.
(b) If NO voltage check fuse 3 of the Junction
Block (JB).
(c) If incorrect voltage, repair as necessary. 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.
(5) Insert a jumper wire between terminal 30 and
87 of the Junction Block (JB).
(a) If horn sounds replace relay.
(b) If the horn does not sound, install horn relay
and test horn (Refer to 8 - ELECTRICAL/HORN/
HORN - DIAGNOSIS AND TESTING).
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel end cap.
(3) Locate and pull the horn relay from the Junc-
tion Block (JB).
INSTALLATION
(1) Locate proper connector, and press relay into
position.
(2) Install instrument panel end cap.
(3) Connect battery negative cable.
Fig. 2 HORN MOUNTING
1 - POWER DISTRIBUTION CENTER
2 - LOW NOTE HORN
3 - HIGH NOTE HORN
Fig. 3 Horn Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
KJHORN 8H - 3
HORN (Continued)

HORN SWITCH
DESCRIPTION
The horn switch is molded into the driver airbag
assembly. The horn switch can not be serviced sepa-
rately. For service procedures, (Refer to 8 - ELEC-
TRICAL/RESTRAINTS/DRIVER AIRBAG -
REMOVAL).
DIAGNOSIS AND TESTING - HORN SWITCH
For complete circuit diagrams, refer to the appro-
priate 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 connec-
tors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the steering column opening cover.
(3) Check for continuity between the metal steer-
ing column jacket and a good ground. There should
be continuity. If OK, go to Step 4. If not OK,(Refer to
19 - STEERING/COLUMN - INSTALLATION) for
proper installation of the steering column.
(4) Remove the driver side airbag module from the
steering wheel (Refer to 8 - ELECTRICAL/RE-
STRAINTS/DRIVER AIRBAG - REMOVAL). Discon-
nect the horn switch wire harness connectors from
the driver side airbag module (Fig. 4).
(5) Remove the horn relay from the Junction Block
(JB). Check for continuity between the steering col-umn half of the horn switch feed wire harness con-
nector and a good ground. There should be no
continuity. If OK, go to Step 6. If not OK, repair the
shorted horn relay control circuit to the horn relay in
the Junction Block as required.
(6) Check for continuity between the steering col-
umn half of the horn switch feed wire harness con-
nector and the horn relay control circuit cavity for
the horn relay in the Junction Block. There should be
continuity. If OK, go to Step 7. If not OK, repair the
open horn relay control circuit to the horn relay in
the Junction Block as required.
(7) Check for continuity between the horn switch
feed wire and the horn switch ground wire on the
driver side airbag module. There should be no conti-
nuity. If OK, go to Step 8. If not OK, replace the
faulty horn switch.
(8) Depress the center of the driver side airbag
module trim cover and check for continuity between
the horn switch feed wire and the horn switch
ground wire on the driver side airbag module. There
should now be continuity. If not OK, replace the
faulty horn switch (Refer to 8 - ELECTRICAL/RE-
STRAINTS/DRIVER AIRBAG - REMOVAL).
Fig. 4 Driver Airbag Housing
1 - HOUSING
2 - HORN SWITCH GROUND WIRE
3 - HORN SWITCH FEED WIRE
4 - INFLATOR
5 - TRIM COVER
8H - 4 HORNKJ