Front light JEEP LIBERTY 2002 KJ / 1.G Owner's Manual

BRAKES - ABS
TABLE OF CONTENTS
page page
BRAKES - ABS
DESCRIPTION.........................32
OPERATION...........................32
DIAGNOSIS AND TESTING - ANTILOCK
BRAKING SYSTEM....................33
STANDARD PROCEDURE - ABS BRAKE
BLEEDING...........................33
SPECIFICATIONS.......................33
ELECTRICAL
DESCRIPTION.........................34
OPERATION...........................34FRONT WHEEL SPEED SENSOR
REMOVAL.............................34
INSTALLATION.........................34
REAR WHEEL SPEED SENSOR
REMOVAL.............................35
INSTALLATION.........................35
HCU (HYDRAULIC CONTROL UNIT)
DESCRIPTION.........................35
OPERATION...........................35
REMOVAL.............................36
INSTALLATION.........................36
BRAKES - ABS
DESCRIPTION
ANTILOCK BRAKING SYSTEM
The purpose of the antilock system is to prevent
wheel lockup during periods of high wheel slip. Pre-
venting lockup helps maintain vehicle braking action
and steering control.
The antilock CAB activates the system whenever
sensor signals indicate periods of high wheel slip.
High wheel slip can be described as the point where
wheel rotation begins approaching 20 to 30 percent of
actual vehicle speed during braking. Periods of high
wheel slip occur when brake stops involve high pedal
pressure and rate of vehicle deceleration.
Battery voltage is supplied to the CAB ignition ter-
minal when the ignition switch is turned to Run posi-
tion. The CAB performs a system initialization
procedure at this point. Initialization consists of a
static and dynamic self check of system electrical
components.
The static check occurs after the ignition switch is
turned to Run position. The dynamic check occurs
when vehicle road speed reaches approximately 30
kph (18 mph). During the dynamic check, the CAB
briefly cycles the pump and solenoids to verify oper-
ation.
If an ABS component exhibits a fault during ini-
tialization, the CAB illuminates the amber warning
light and registers a fault code in the microprocessor
memory.
ELECTRONIC BRAKE DISTRIBUTION
The electronic brake distribution (EBD) functions
like a rear proportioning valve. The EBD system usesthe ABS system to control the slip of the rear wheels
in partial braking range. The braking force of the
rear wheels is controlled electronically by using the
inlet and outlet valves located in the HCU.
OPERATION
ANTILOCK BRAKING SYSTEM
During normal braking, the master cylinder, power
booster and wheel brake units all function as they
would in a vehicle without ABS. The HCU compo-
nents are not activated.
During antilock braking fluid pressure is modu-
lated according to wheel speed, degree of slip and
rate of deceleration. A sensor at each wheel converts
wheel speed into electrical signals. These signals are
transmitted to the CAB for processing and determi-
nation of wheel slip and deceleration rate.
The ABS system has three fluid pressure control
channels. The front brakes are controlled separately
and the rear brakes in tandem. A speed sensor input
signal indicating a high slip condition activates the
CAB antilock program. Two solenoid valves are used
in each antilock control channel. The valves are all
located within the HCU valve body and work in pairs
to either increase, hold, or decrease apply pressure as
needed in the individual control channels. The sole-
noid valves are not static during antilock braking.
They are cycled continuously to modulate pressure.
Solenoid cycle time in antilock mode can be mea-
sured in milliseconds.
ELECTRONIC BRAKE DISTRIBUTION
Upon entry into EBD the inlet valve for the rear
brake circuit is switched on so that the fluid supply
from the master cylinder is shut off. In order to
decrease the rear brake pressure the outlet valve for
5 - 32 BRAKES - ABSKJ

CONDITION POSSIBLE CAUSES CORRECTION
Clutch pedal squeak. 1. Pivot pin loose. 1. Tighten pivot pin if possible.
Replace clutch pedal if necessary.
2. Master cylinder bushing not
lubricated.2. Lubricate master cylinder
bushing.
3. Pedal bushings worn out or
cracked.3. Replace and lubricate bushings.
Clutch master or slave cylinder
plunger dragging andùr binding1. Master or slave cylinder
components worn or corroded.1. Replace clutch hydraulic linkage
assembly.
Release bearing is noisy. 1. Release bearing defective or
damaged.1. Replace release bearing.
Contact surface of release bearing
damaged.1. Clutch cover incorrect or release
fingers bent or distorted.1. Replace clutch cover and release
bearing.
2. Release bearing defective or
damaged.2. Replace the release bearing.
3. Release bearing misaligned. 3. Check and correct runout of
clutch components. Check front
bearing sleeve for damage/
alignment. Repair as necessary.
Partial engagement of clutch disc.
One side of disc is worn and the
other side is glazed and lightly
worn.1. Clutch pressure plate position
incorrect.1. Replace clutch disc and cover.
2. Clutch cover, spring, or release
fingers bent or distorted.2. Replace clutch disc and cover.
3. Clutch disc damaged or
distorted.2. Replace clutch disc.
4. Clutch misalignment. 4. Check alignment and runout of
flywheel, disc, pressure plate, andùr
clutch housing. Correct as
necessary.
SPECIFICATIONS - CLUTCH
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Pressure Plate Bolts -
2.4L31 23 -
Pressure Plate Bolts -
3.7L50 37 -
Clutch Cylinder Bolts 23 - 200
Flywheel Bolts - 2.4L 81 60 -
Flywheel Bolts - 3.7L 81 60 -
KJCLUTCH 6 - 5
CLUTCH (Continued)

CLUTCH DISC
REMOVAL
(1) Remove transmission.
(2) Mark position of pressure plate on flywheel
with paint or a scriber for assembly reference, if
clutch is not being replaced.
(3) Loosen pressure plate bolts evenly and in rota-
tion to relieve spring tension and avoid warping the
plate.
(4) Remove pressure plate bolts and pressure plate
and disc.
INSTALLATION
(1) Lightly scuff sand flywheel face with 180 grit
emery cloth, then clean with a wax and grease
remover.
(2) Lubricate pilot bearing with Mopar high tem-
perature bearing grease or equivalent.
(3) Check runout and operation ofnewclutch disc.
NOTE: Disc must slide freely on transmission input
shaft splines.
(4) With the disc on the input shaft, check face
runout with dial indicator. Check runout at disc hub
6 mm (1/4 in.) from outer edge of facing. Obtain
another clutch disc if runout exceed 0.5 mm (0.020
in.).
(5) Position clutch disc on flywheel with side
marked flywheel against the flywheel.
NOTE: If not marked, the flat side of disc hub goes
towards the flywheel on the 3.7L engine and
towards the transmission on 2.4L engine.
(6) Insert clutch alignment tool through the clutch
disc and into the pilot bearing (Fig. 1).
(7) Position clutch pressure plate over disc and on
the flywheel (Fig. 1).
(8) Install pressure plate bolts finger tight.
CAUTION: Use only the factory bolts to mount the
pressure plate. The bolts must be the correct size.
If bolts are too short, there isn't enough thread
engagement, if too long bolts interfere with the Dual
Mass Flywheel.
(9) Tighten pressure plate bolts evenly and in rota-
tion a few threads at a time.
CAUTION: The bolts must be tightened evenly and
to specified torque to avoid distorting the pressure
plate.(10) Tighten pressure plate bolts to 31 N´m (23 ft.
lbs.) on 2.4L engines and 50 N´m (37ft. lbs.) on 3.7L
engines.
(11) Apply light coat of Mopar high temperature
bearing grease or equivalent to clutch disc hub and
splines of transmission input shaft.
CAUTION: Do not over lubricate shaft splines. This
will result in grease contamination of disc.
(12) Install transmission.
CLUTCH RELEASE BEARING
REMOVAL
(1) Remove transmission.
(2) Disconnect release bearing from release lever
and remove the bearing (Fig. 2).
(3) Inspect bearing slide surface of transmission
front bearing retainer. Replace retainer if slide sur-
face is scored, worn, or cracked.
(4) Inspect release fork and fork pivot. Be sure
pivot is secure and in good condition. Be sure fork is
not distorted or worn. Replace release fork retainer
spring if bent or damaged.
INSTALLATION
(1) Lubricate crankshaft pilot bearing with Mopar
high temperature bearing grease or equivalent. Apply
grease to end of long shank, small diameter flat
blade screwdriver. Then insert tool through clutch
disc hub to reach bearing.
Fig. 1 ALIGNING CLUTCH DISC
1 - FLYWHEEL
2 - PRESSURE PLATE
3 - CLUTCH DISC ALIGNMENT TOOL
6 - 6 CLUTCHKJ

The ECT sensor is a two-wire Negative Thermal
Coefficient (NTC) sensor. Meaning, as engine coolant
temperature increases, resistance (voltage) in the
sensor decreases. As temperature decreases, resis-
tance (voltage) in the sensor increases.
OPERATION
At key-on, the Powertrain Control Module (PCM)
sends out a regulated 5 volt signal to the ECT sensor.
The PCM then monitors the signal as it passes
through the ECT sensor to the sensor ground (sensor
return).
When the engine is cold, the PCM will operate in
Open Loop cycle. It will demand slightly richer air-
fuel mixtures and higher idle speeds. This is done
until normal operating temperatures are reached.
The PCM uses inputs from the ECT sensor for the
following calculations:
²for engine coolant temperature gauge operation
through CCD or PCI (J1850) communications
²Injector pulse-width
²Spark-advance curves
²ASD relay shut-down times
²Idle Air Control (IAC) motor key-on steps
²Pulse-width prime-shot during cranking
²O2 sensor closed loop times
²Purge solenoid on/off times
²EGR solenoid on/off times (if equipped)
²Leak Detection Pump operation (if equipped)
²Radiator fan relay on/off times (if equipped)
²Target idle speed
REMOVAL
2.4L
The Engine Coolant Temperature (ECT) sensor is
installed into a water jacket at left front of cylinder
head (Fig. 1).
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.
(1) Partially drain cooling system.
(2) Disconnect electrical connector from sensor.
(3) Remove sensor from cylinder head.
3.7L
The Engine Coolant Temperature (ECT) sensor is
installed into a water jacket at front of intake mani-
fold near rear of generator (Fig. 2).
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.(1) Partially drain cooling system.
(2) Disconnect electrical connector from sensor.
(3) Remove sensor from intake manifold.
Fig. 1 ECT AND UPPER TIMING BELT COVER/
BOLTS-2.4L
1 - UPPER TIMING BELT COVER
2 - ELECTRICAL CONNECTOR (ECT)
3 - MOUNTING BOLTS (3)
Fig. 2 MAP SENSOR / ECT SENSOR - 3.7L
1 - MOUNTING SCREWS
2 - MAP SENSOR
3 - ECT SENSOR
7 - 20 ENGINEKJ
ENGINE COOLANT TEMPERATURE SENSOR (Continued)

Only when sufficient heat is present, will the vis-
cous fan drive engage. This is when the air flowing
through the radiator core causes a reaction to the
bimetallic coil. It then increases fan speed to provide
the necessary additional engine cooling.
Once the engine has cooled, the radiator discharge
temperature will drop. The bimetallic coil again
reacts and the fan speed is reduced to the previous
disengaged speed.
DIAGNOSIS AND TESTING - VISCOUS FAN
DRIVE
If the fan assembly free-wheels without drag (the
fan blades will revolve more than five turns when
spun by hand), replace the fan drive. This spin test
must be performed when the engine is cool.
For the following test, the cooling system must be
in good condition. It also will ensure against exces-
sively high coolant temperature.
WARNING: BE SURE THAT THERE IS ADEQUATE
FAN BLADE CLEARANCE BEFORE DRILLING.
(1) Drill a 3.18-mm (1/8-in) diameter hole in the
top center of the fan shroud.
(2) Obtain a dial thermometer with an 8 inch stem
(or equivalent). It should have a range of -18É to
105ÉC (0É to 220É F). Insert thermometer through the
hole in the shroud. Be sure that there is adequate
clearance from the fan blades.
(3) Connect a tachometer and an engine ignition
timing light (timing light is to be used as a strobe
light).
(4) Block the air flow through the radiator. Secure
a sheet of plastic in front of the radiator (or air con-
ditioner condenser). Use tape at the top to secure the
plastic and be sure that the air flow is blocked.
(5) Be sure that the air conditioner (if equipped) is
turned off.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(6) Start the engine and operate at 2400 rpm.
Within ten minutes the air temperature (indicated on
the dial thermometer) should be up to 93É C (200É F).
Fan driveengagementshould have started to occur
at between 91É to 96É C (195É to 205É F). Engage-
ment is distinguishable by a definiteincreasein fan
flow noise (roaring). The timing light also will indi-
cate an increase in the speed of the fan.
(7) When the air temperature reaches 93É C (200É
F), remove the plastic sheet. Fan drivedisengage-
mentshould have started to occur at between 62É to85É C (145É to 185É F). A definitedecreaseof fan
flow noise (roaring) should be noticed. If not, replace
the defective viscous fan drive unit.
REMOVAL
(1) Disconnect negative battery cable from battery.
NOTE: The thermal viscous fan drive/fan blade
assembly is attached (threaded) to water pump hub
shaft.
(2) Remove fan blade/viscous fan drive assembly
from water pump using special tool 6958 spanner
wrench and 8346 adapters, by turning mounting nut
counterclockwise as viewed from front (Fig. 16).
Threads on viscous fan drive areRIGHT HAND.
(3) Do not attempt to remove fan/viscous fan drive
assembly from vehicle at this time.
(4) Do not unbolt fan blade assembly from viscous
fan drive at this time.
(5) Remove fan shroud to radiator bolts.
(6) Remove fan shroud and fan blade/viscous fan
drive assembly as a complete unit from vehicle.
(7) After removing fan blade/viscous fan drive
assembly,do notplace viscous fan drive in horizon-
tal position. If stored horizontally, silicone fluid in
the viscous fan drive could drain into its bearing
assembly and contaminate lubricant.
Fig. 16 Viscous Fan and Fan Drive 3.7L
1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER
PINS 8346
2-FAN
7 - 28 ENGINEKJ
RADIATOR - FAN - VISCOUS (Continued)

ENGINE COOLANT
TEMPERATURE SENSOR
DESCRIPTION
The Engine Coolant Temperature (ECT) sensor is
used to sense engine coolant temperature. The sensor
protrudes into an engine water jacket.
The ECT sensor is a two-wire Negative Thermal
Coefficient (NTC) sensor. Meaning, as engine coolant
temperature increases, resistance (voltage) in the
sensor decreases. As temperature decreases, resis-
tance (voltage) in the sensor increases.
OPERATION
At key-on, the Powertrain Control Module (PCM)
sends out a regulated 5 volt signal to the ECT sensor.
The PCM then monitors the signal as it passes
through the ECT sensor to the sensor ground (sensor
return).
When the engine is cold, the PCM will operate in
Open Loop cycle. It will demand slightly richer air-
fuel mixtures and higher idle speeds. This is done
until normal operating temperatures are reached.
The PCM uses inputs from the ECT sensor for the
following calculations:
²for engine coolant temperature gauge operation
through CCD or PCI (J1850) communications
²Injector pulse-width²Spark-advance curves
²ASD relay shut-down times
²Idle Air Control (IAC) motor key-on steps
²Pulse-width prime-shot during cranking
²O2 sensor closed loop times
²Purge solenoid on/off times
²EGR solenoid on/off times (if equipped)
²Leak Detection Pump operation (if equipped)
²Radiator fan relay on/off times (if equipped)
²Target idle speed
REMOVAL
2.4L
The Engine Coolant Temperature (ECT) sensor is
installed into a water jacket at left front of cylinder
head (Fig. 2).
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.
(1) Partially drain cooling system.
(2) Disconnect electrical connector from sensor.
(3) Remove sensor from cylinder head.
3.7L
The Engine Coolant Temperature (ECT) sensor is
installed into a water jacket at front of intake mani-
fold near rear of generator (Fig. 3).
Fig. 1 ENGINE BLOCK HEATER 2.4L
1 - CORE HOLE
2 - BLOCK HEATER
3 - POWER CORD
Fig. 2 ECT AND UPPER TIMING BELT COVER/
BOLTS-2.4L
1 - UPPER TIMING BELT COVER
2 - ELECTRICAL CONNECTOR (ECT)
3 - MOUNTING BOLTS (3)
KJENGINE7s-21
ENGINE BLOCK HEATER - 2.4L (Continued)

economy, and/or trip odometer data has been reset.
The CMTC uses internal programming, hard wired
inputs from the U.S./Metric and Reset switches, and
electronic messages received from the Body Control
Module (BCM) to determine the proper reset mes-
sages to send to the EMIC.
²Door Ajar Warning- The EMIC chime tone
generator will generate a single ªbong-likeº chime
tone when the ignition switch is in the On position,
and electronic messages are received over the PCI
data bus from the Body Control Module (BCM) indi-
cating that the status of any door ajar input has
changed from closed to not closed, and from the PCM
indicating that the vehicle is moving. The BCM uses
internal programming, and hard wired inputs from
the door ajar switches and the ignition switch to
determine the proper door ajar switch messages to
send to the EMIC. The PCM uses internal program-
ming and a hard wired vehicle speed pulse input
received from the BCM to determine the proper vehi-
cle distance messages to send to the EMIC.
²Electrical System Voltage Low or High
Warning- Each time the ignition switch is turned to
the On position, the EMIC chime tone generator will
generate a single ªbong-likeº chime tone the first
time an electronic message is received over the PCI
data bus from the PCM requesting ªChargingº indi-
cator illumination. This warning would indicate that
the monitored electrical system voltage is either too
low or too high. This warning will only occur once
during an ignition cycle. The PCM uses internal pro-
gramming and hard wired inputs from the electrical
and charging systems to determine the proper
ªChargingº indicator messages to send to the EMIC.
²Engine Coolant Temperature High Warning
- Each time the ignition switch is turned to the On
position, the EMIC chime tone generator will gener-
ate ªbong-likeº chime tones the first time an elec-
tronic message is received over the PCI data bus
from the PCM indicating that the engine coolant
temperature is too high. This chime will sound for
five consecutive single tones, unless an electronic
message is received from the PCM indicating that
the engine coolant temperature is not too high, or
unless the ignition switch is turned to the Off posi-
tion before the five single tones have completed. The
PCM uses internal programming and a hard wired
input from the engine coolant temperature sensor to
determine the proper engine coolant temperature
messages to send to the EMIC.
²Engine Oil Pressure Low Warning- Each
time the ignition switch is turned to the On position,
the EMIC chime tone generator will generate a sin-
gle ªbong-likeº chime tone the first time three
sequential sets of electronic messages are received
over the PCI data bus from the PCM indicating thatthe engine oil pressure is too low with the engine
running. The PCM uses internal programming and
hard wired inputs from the oil pressure sensor and
the crankshaft position sensor to determine the
proper oil pressure and engine speed messages to
send to the EMIC.
²Fasten Seat Belt Warning- Each time the
ignition switch is turned to the On position, the
EMIC chime tone generator will generate repetitive
ªbong-likeº chime tones at a slow rate the first time
an electronic message is received over the PCI data
bus from the ACM requesting ªSeatbeltº indicator
illumination. The ACM uses internal programming
and hard wired inputs from the driver side front seat
belt switch and the ignition switch to determine that
the driver side front seat belt is not fastened with
the ignition switch in the On position. These chimes
will continue to sound for a duration of about six sec-
onds each time the ignition switch is turned to the
On position, or until the driver side front seat belt is
fastened, whichever occurs first. This audible warn-
ing occurs independent of the visual warning pro-
vided by the EMIC ªSeatbeltº indicator.
²Gate Ajar Warning- The EMIC chime tone
generator will generate a single ªbong-likeº chime
tone when the ignition switch is in the On position,
and electronic messages are received over the PCI
data bus from the BCM indicating that the status of
the tailgate ajar input has changed from closed to
not closed, and from the PCM indicating that the
vehicle is moving. The BCM uses internal program-
ming, and hard wired inputs from the tailgate ajar
switch and the ignition switch to determine the
proper tailgate ajar switch messages to send to the
EMIC. The PCM uses internal programming and a
hard wired vehicle speed pulse input received from
the BCM to determine the proper vehicle distance
messages to send to the EMIC.
²Glass Ajar Warning- The EMIC chime tone
generator will generate a single ªbong-likeº chime
tone when the ignition switch is in the On position,
and electronic messages are received over the PCI
data bus from the BCM indicating that the status of
the rear flip-up glass ajar input has changed from
closed to not closed, and from the PCM indicating
that the vehicle is moving. The BCM uses internal
programming, and hard wired inputs from the flip-up
glass ajar switch and the ignition switch to deter-
mine the proper flip-up glass ajar switch messages to
send to the EMIC. The PCM uses internal program-
ming and a hard wired vehicle speed pulse input
received from the BCM to determine the proper vehi-
cle distance messages to send to the EMIC.
²Head/Park/Fog Lights-On Warning- The
EMIC chime tone generator will generate repetitive
ªbong-likeº chime tones at a fast rate when the igni-
KJCHIME/BUZZER 8B - 3
CHIME WARNING SYSTEM (Continued)

tion switch is in any position except On, and elec-
tronic messages are received over the PCI data bus
from the BCM indicating that the exterior lights are
On with the ignition switch in any position except
On, and the status of the driver side front door is not
closed. The BCM uses internal programming and
hard wired inputs from the left (lighting) control
stalk of the multi-function switch, the ignition
switch, and the driver side front door ajar switch to
determine the proper messages to send to the EMIC.
These chimes will continue to sound until the exte-
rior lighting is turned Off, until the ignition switch is
turned to the On position, or until the status of the
driver side front door ajar input changes from not
closed to closed, whichever occurs first.
²Key-In-Ignition Warning- The EMIC chime
tone generator will generate repetitive ªbong-likeº
chime tones at a fast rate when the ignition switch is
in any position except On, and electronic messages
are received over the PCI data bus from the BCM
indicating that the key is in the ignition lock cylinder
with the ignition switch in any position except On,
and the driver side front door is not closed. The BCM
internal programming and hard wired inputs from
the key-in ignition circuitry of the ignition switch,
the ignition switch, and the driver side front door
ajar switch to determine the proper messages to send
to the EMIC. These chimes will continue to sound
until the key is removed from the ignition lock cylin-
der, until the ignition switch is turned to the On
position, or until the status of the driver side front
door ajar input changes from not closed to closed,
whichever occurs first.
²Low Coolant Warning- On vehicles equipped
with a diesel engine, the EMIC chime tone generator
will generate a single ªbong-likeº chime tone when
the ignition switch is first turned to the On position
and a hard wired input from the engine coolant level
sensor to the EMIC indicates that the coolant level is
low for more than about one-quarter second. Any
time after the ignition switch is first turned to the
On position, the EMIC uses internal programming to
check the status of the engine coolant level sensor
inputs about once every second, then adjusts an
internal counter up or down based upon the status of
this input. When the counter accumulates thirty
inputs indicating that the coolant level is low, a sin-
gle chime tone is sounded. This strategy is intended
to reduce the effect that coolant sloshing within the
coolant reservoir can have on reliable chime warning
operation. This warning will only occur once during
an ignition cycle.
²Low Fuel Warning- Each time the ignition
switch is turned to the On position, the EMIC chime
tone generator will generate a single ªbong-likeº
chime tone the first time an electronic message isreceived over the PCI data bus from the PCM
requesting ªLow Fuelº indicator illumination. The
chime will only occur a second time during the same
ignition cycle if another electronic message has been
received from the PCM indicating that there is an
increase in the fuel level equal to about 3 liters (0.8
gallon), then a subsequent electronic message from
the PCM requests ªLow Fuelº indicator illumination.
This strategy combined with filtering performed by
the internal programming of the PCM on the fuel
tank sending unit input is intended to reduce the
possibility of fuel sloshing within the fuel tank caus-
ing multiple low fuel warning chimes during a given
ignition cycle. The EMIC will also respond with the
low fuel warning chime when electronic fuel level
messages are received from the PCM indicating that
the hard wired input to the PCM from the fuel tank
sending unit is an open circuit (greater than full), or
a short circuit (less than empty).
²Low Washer Fluid Warning- The EMIC
chime tone generator will generate a single ªbong-
likeº chime tone when the ignition switch is turned
to the On position and a hard wired input from the
washer fluid level switch to the EMIC indicates the
washer fluid is low for more than about one-quarter
second. Any time after the ignition switch is first
turned to the On position, the EMIC uses internal
programming to check the status of the washer fluid
level switch inputs about once every second, then
adjusts an internal counter up or down based upon
the status of this input. When the counter accumu-
lates thirty inputs indicating that the washer fluid
level is low, a single chime tone is sounded. This
strategy is intended to reduce the effect that fluid
sloshing within the washer reservoir can have on
reliable chime warning operation. This warning will
only occur once during an ignition cycle.
²Overspeed Warning- The EMIC chime tone
generator will generate repetitive ªbong-likeº chime
tones at a slow rate when the ignition switch is in
the On position, and an electronic message received
over the PCI data bus from the PCM indicates that
the vehicle speed is over a programmed speed value.
The PCM uses internal programming and distance
pulse information received over a hard wired vehicle
speed pulse input from the BCM to determine the
proper vehicle speed messages to send to the EMIC.
The BCM uses an internally programmed electronic
pinion factor and a hard wired input from the rear
wheel speed sensor to calculate the proper distance
pulse information to send to the PCM. The electronic
pinion factor represents the proper tire size and axle
ratio information for the vehicle. These chimes will
continue to sound until the vehicle speed messages
are below the programmed speed value, or until the
ignition switch is turned to the Off position, which-
8B - 4 CHIME/BUZZERKJ
CHIME WARNING SYSTEM (Continued)

There are two different versions of the BCM: base
and premium. The base BCM is a subset of the com-
ponents in the premium version. Basically, the base
version BCM does not support the following features:
Compass Mini-Trip Computer (CMTC), fog lamps
(front and/or rear), Remote Keyless Entry (RKE),
remote radio switches, or Vehicle Theft Security Sys-
tem (VTSS). Both versions of the BCM utilize inte-
grated circuitry and information carried on the
Programmable Communications Interface (PCI) databus network along with many hard wired inputs to
monitor many sensor and switch inputs throughout
the vehicle. In response to those inputs, the internal
circuitry and programming of the BCM allow it to
control and integrate many electronic functions and
features of the vehicle through both hard wired out-
puts and the transmission of electronic message out-
puts to other electronic modules in the vehicle over
the PCI data bus. The electronic functions and fea-
tures that the BCM supports or controls include the
following:
²A/C Select Switch Status- The BCM monitors
an input from, and transmits the status of the A/C
switch on the heater-A/C control.
²Ambient Temperature Data- The premium
BCM monitors and transmits the ambient tempera-
ture sensor input data.
²Cargo Lamp Disable- The BCM monitors an
input from the cargo lamp switch to provide an inte-
rior lighting disable feature.
²Chimes- The chime tone generator is located
on the ElectroMechanical Instrument Cluster (EMIC)
circuit board, but the EMIC goes to sleep with the
ignition switch in the Off position. The BCM provides
a wake-up output to the EMIC based upon inputs
from the key-in ignition switch or the exterior light-
ing switch, then sends electronic chime request mes-
sages to the EMIC for the headlamps-on warning
and key-in ignition warning.
²Door Lock Inhibit- The BCM monitors the
key-in ignition switch and the driver side front door
ajar switch to provide a door lock inhibit feature.
²Exterior Lamp Load Shedding- The BCM
provides a battery saver feature which will automat-
ically turn off exterior lamps that remain on after a
timed interval.
²Exterior Lamp Status- The BCM monitors
the status of the park lamp, low beam, high beam or
Daytime Running Lamp (DRL - Canada only), front
fog lamp (optional), and rear fog lamp (in required
markets only) relays.
²Exterior Lighting Control- The BCM pro-
vides exterior lamp control for standard head and
park lamps, as well as Daytime Running Lamps
(DRL - Canada only), front fog lamps (optional), and
rear fog lamps (in required markets only). This
includes support for features including optical horn
(also known as flash-to-pass) and headlamp time
delay.
²Flip-Up Glass Control- The BCM monitors
the tailgate cylinder lock switch, the tailgate handle
switch, the Remote Keyless Entry (RKE) module
inputs and the rear wiper switch to provide control
for the rear flip-up glass actuator.
Fig. 1 Body Control Module Location
1 - DRIVER DOOR
2 - INSTRUMENT PANEL END BRACKET
3 - JUNCTION BLOCK
4 - BODY CONTROL MODULE
Fig. 2 Body Control Module
1 - BODY CONTROL MODULE (FRONT VIEW)
2 - REMOTE KEYLESS ENTRY MODULE RECEPTACLE
3 - BCM-RKE CONNECTOR
4 - BODY CONTROL MODULE (BACK VIEW)
5 - JB-BCM CONNECTOR
6 - CONNECTOR RECEPTACLE (2)
KJELECTRONIC CONTROL MODULES 8E - 3
BODY CONTROL MODULE (Continued)

²Fog Lamp Control- The premium BCM pro-
vides fog lamp control for front fog lamps (optional),
and rear fog lamps (in required markets only).
²Front Wiper System Status- The BCM moni-
tors the status of the front wiper motor park switch.
²Fuel Economy and Distance to Empty Cal-
culations- The BCM calculates and transmits the
fuel economy and Distance To Empty (DTE) data.
²Headlamp Time Delay- The BCM provides a
headlamp time delay feature with the ignition switch
in the Off position.
²Heated Rear Glass Control- The BCM pro-
vides control and timer functions for the heated rear
glass feature and transmits the system status.
²Ignition On/Off Timer- The BCM monitors
and transmits the elapsed ignition On timer data
and monitors the ignition Off time.
²Ignition Switch Position Status- The BCM
monitors and transmits the status of the ignition
switch.
²Instrument Panel Dimming- The BCM mon-
itors and transmits the selected illumination inten-
sity level of the panel lamps dimmer switch.
²Interior Lamp Load Shedding- The BCM
provides a battery saver feature which will automat-
ically turn off all interior lamps that remain on after
a timed interval.
²Interior Lighting Control- The BCM moni-
tors inputs from the interior lighting switch, the door
ajar switches, the flip-up glass ajar switch, the tail-
gate ajar switch, the cargo lamp switch, the reading
lamp switches, and the Remote Keyless Entry (RKE)
module to provide courtesy lamp control. This
includes support for timed illuminated entry with
theater-style fade-to-off and courtesy illumination
defeat features.
²Intermittent Wipe and Front Wiper System
Control- The BCM monitors inputs from the front
wiper and washer switch and the front wiper motor
park switch to provide front wiper system control
through the wiper on/off and high/low relays. This
includes support for adjustable intermittent wipe,
mist wipe (also known as pulse wipe), and wipe-after-
wash features.
²Key-In-Ignition Switch Status- The BCM
monitors and transmits the status of the key-in-igni-
tion switch.
²Panic Mode- The BCM provides support for
the Remote Keyless Entry (RKE) system panic mode
feature.
²Parade Mode- The BCM provides a parade
mode (also known as funeral mode) that allows the
interior Vacuum Fluorescent Displays (VFD) to be
illuminated at full intensity while driving in daylight
with the exterior lamps On.²Power Locks- The BCM monitors inputs from
the power lock switches and the Remote Keyless
Entry (RKE) module (optional) to provide control of
the power lock motors through outputs to the lock,
unlock, and driver unlock (RKE only) relays. This
includes support for rolling door locks (also known as
automatic door locks) and a door lock inhibit mode.
²Programmable Features- The BCM provides
support for several standard and optional program-
mable features, including: rolling door locks, head-
lamp time delay interval, Remote Keyless Entry
(RKE) driver-door-only or unlock-all-doors, RKE opti-
cal chirp, and RKE audible chirp.
²Remote Keyless Entry- The premium BCM
provides the optional Remote Keyless Entry (RKE)
system features, including support for the RKE Lock,
Unlock (with optional driver-door-only unlock, and
unlock-all-doors), rear flip-up glass control, Panic,
audible chirp, optical chirp, and illuminated entry
modes, as well as the ability to be programmed to
recognize up to four RKE transmitters.
²Rolling Door Locks- The BCM provides sup-
port for the power lock system rolling door locks fea-
ture (also known as automatic door locks).
²Tailgate and Flip-Up Glass Ajar Status- The
BCM monitors and transmits the status of the tail-
gate and rear flip-up glass ajar switches.
²Remote Radio Switch Interface- The pre-
mium BCM monitors and transmits the status of the
optional remote radio switches.
²Self-Diagnostics- The BCM provides support
for diagnostics through communication with the
DRBIIItscan tool over the PCI data bus network.
Each analog and digital input can be verified, and
each output can be actuated through the use of this
diagnostic protocol. The BCM also stores Diagnostic
Trouble Codes (DTCs) to assist in troubleshooting
this unit.
²Vacuum Fluorescent Display Synchroniza-
tion- The BCM transmits panel lamp intensity data
which allows modules with Vacuum Fluorescent Dis-
plays (VFD) to coordinate their illumination inten-
sity.
²Vehicle Speed System- The BCM monitors a
vehicle speed input from the vehicle speed sensor
(without Antilock Brake System [ABS]) or from the
Controller Antilock Brake (CAB)(with ABS), calcu-
lates the vehicle speed based upon a programmed
axle ratio/tire size (electronic pinion factor), and
transmits the vehicle speed information to the Pow-
ertrain Control Module (PCM) on a hard wired out-
put circuit.
²Vehicle Theft Security System- The pre-
mium BCM monitors inputs from the door cylinder
lock switches, the tailgate cylinder lock switch, the
door ajar switches, the tailgate ajar switch, the
8E - 4 ELECTRONIC CONTROL MODULESKJ
BODY CONTROL MODULE (Continued)