ICU (INTEGRATED CONTROL
UNIT)
DESCRIPTION
The hydraulic control unit (HCU) and the control-
ler antilock brake (CAB) used with this antilock
brake system are combined (integrated) into one
unit, which is called the integrated control unit (ICU)
(Fig. 12). The ICU is located below the master cylin-
der in the engine compartment (Fig. 13).
Two different ICU's (HCU and CAB) are used on
this vehicle depending on whether or not the vehicle
is equipped with traction control. The HCU on avehicle equipped with traction control has a valve
block that is approximately one inch longer than a
HCU on a vehicle that is equipped with ABS only.
The ABS-only ICU consists of the following compo-
nents: the CAB, eight (build/decay) solenoid valves
(four inlet valves and four outlet valves), valve block,
fluid accumulators, a pump, and an electric motor.
The ABS-with traction control ICU consists of the
following components: the CAB, eight (build/decay)
solenoid valves (four inlet valves and four outlet
valves), two traction control (ASR) valves, two
hydraulic shuttle valves, valve block, fluid accumula-
tors, a pump, and an electric motor.
The replaceable components of the ICU are the
HCU and the CAB. No attempt should be made to
service any individual components of the HCU or
CAB. For information on the CAB, (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/CONTROLLER ANTILOCK BRAKE -
DESCRIPTION).
OPERATION
For information of the ICU, refer to these individ-
ual components of the ICU:
²CONTROLLER ANTILOCK BRAKE (CAB)
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/CONTROLLER ANTILOCK
BRAKE - OPERATION)
²HYDRAULIC CONTROL UNIT (HCU) (Refer to
5 - BRAKES - ABS/HYDRAULIC/MECHANICAL/
HCU (HYDRAULIC CONTROL UNIT) - OPERA-
TION)
For information on the ICU's hydraulic circuits,
refer to HYDRAULIC CIRCUITS AND VALVE
OPERATION. (Refer to 5 - BRAKES - ABS/HY-
DRAULIC/MECHANICAL - OPERATION)
REMOVAL
REMOVAL - LHD
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Remove the battery shield.
(3) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(4) Disconnect the vacuum hose connector at the
tank built into the battery tray.
(5) Remove the screw securing the engine coolant
filler neck to the battery tray.
(6) Remove the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - REMOVAL).
(7) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
Fig. 12 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 13 ICU LOCATION IN VEHICLE
1 - POWER BRAKE BOOSTER
2 - MASTER CYLINDER
3 - ICU
5 - 102 BRAKES - ABSRS
draining out of the master cylinder once the
brake tubes are removed from the HCU.
CAUTION: Do not apply a 12±volt power source to
any terminals of the 24-way CAB connector when
disconnected.
(8) Disconnect the wiring harness connector from
the speed control servo.
(9) Remove the speed control servo mounting nuts
and move the servo out of the way.
(10) Disconnect the 24±way connector from the
CAB. To disconnect the 24±way connector, grasp the
lock on the 24±way connector and pull it as far up as
possible. This will unlock the 24±way connector from
the socket on the CAB.
CAUTION: Before removing the brake tubes from
the HCU, the HCU must be thoroughly cleaned. This
must be done to prevent dirt particles from falling
into the ports of HCU or entering the brake tubes.
(11) Thoroughly clean all surfaces of the ICU and
brake tube nuts. Use only a solvent such as Mopart
Brake Parts Cleaner or equivalent to clean the ICU.
(12) Remove the brake tubes (4) from the outlet
ports on the HCU (Fig. 14).
(13) Remove the primary and secondary brake
tubes from the inlet ports on the HCU (Fig. 14).
(14) Center and prop the steering wheel.
(15) Remove the pinch bolt and disconnect the
steering shaft coupling.
(16) If equipped, remove the two clips securing
silencer to dash seal (Fig. 15). Remove silencer.
(17) Remove the three screws securing the dash
seal (Fig. 15). Remove seal.(18) Remove the 3 bolts attaching the ICU to its
mounting bracket (Fig. 16).
(19) Remove ICU from the vehicle through engine
compartment.
(20) If required, to separating the CAB from the
HCU, (Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-
Fig. 14 Brake Tube Nuts At ICU
1 - PRIMARY BRAKE TUBE
2 - SECONDARY BRAKE TUBE
3 - CHASSIS BRAKE TUBES
Fig. 15 Lower Coupling And Dash Seal
1 - COUPLING
2 - DASH SEAL
3 - SILENCER
4 - MOUNTING SCREWS
5 - RETAINING CLIPS
6 - DASH
Fig. 16 ICU Mounting Bolts
1 - ICU MOUNTING BOLTS
2 - COUPLER
RSBRAKES - ABS5 - 103
ICU (INTEGRATED CONTROL UNIT) (Continued)
CHANICAL/ICU (INTEGRATED CONTROL UNIT) -
DISASSEMBLY).
REMOVAL - RHD
NOTE: Before proceeding, (Refer to 5 - BRAKES -
WARNING)(Refer to 5 - BRAKES - CAUTION)
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
draining out of the master cylinder when the
brake tubes are removed from the HCU.
(3) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(4) Remove the routing clip attaching the ICU wir-
ing harness to the ICU mounting bracket (Fig. 17).
CAUTION: Do not apply a 12 volt power source to
any terminals of the HCU connector when discon-
nected.
(5) Remove the 24-way connector (Fig. 17) from
the CAB. The 24-way connector is removed from the
CAB using the following procedure. Grasp the lock
on the 24-way connector (Fig. 17) and pull it as far
out as possible (Fig. 18). This will raise and unlock
the 24-way connector from the socket on the CAB.
CAUTION: Before removing the brake tubes from
the HCU, the HCU must be thoroughly cleaned. Thismust be done to prevent dirt particles from falling
into the ports of HCU or entering the brake tubes.
(6) Thoroughly clean all surfaces of the HCU, and
all brake tube nuts located on the HCU. Use only a
solvent such as Mopar Brake Parts Cleaner or an
equivalent to clean the HCU.
(7) Remove the brake tubes (6) from the inlet and
outlet ports on the HCU. (Fig. 19).
Fig. 17 CAB 24-Way Connector
1 - CAB WIRING HARNESS
2 - 24±WAY CONNECTOR
3 - FLOOR PAN
4 - HCU
5 - CAB
6 - HCU MOUNTING BRACKET
7 - CONNECTOR LOCK
Fig. 18 Unlocked 24-Way CAB Connector
1 - HCU
2 - CAB
3 - 24±WAY CONNECTOR
4 - CONNECTOR LOCK (UNLOCKED)
Fig. 19 Brake Tube Connections To HCU
1 - LEFT REAR WHEEL BRAKE TUBE
2 - SECONDARY BRAKE TUBE FROM MASTER CYLINDER
3 - LEFT FRONT WHEEL BRAKE TUBE
4 - CAB
5 - RIGHT REAR WHEEL BRAKE TUBE
6 - HCU MOUNTING BRACKET
7 - BRAKE TUBE TO HCU CONNECTION LOCATION LEGEND
8 - RIGHT FRONT WHEEL BRAKE TUBE
9 - PRIMARY BRAKE TUBE FROM MASTER CYLINDER
5 - 104 BRAKES - ABSRS
ICU (INTEGRATED CONTROL UNIT) (Continued)
(8) Remove the 3 bolts (Fig. 20) attaching the ICU
mounting bracket to the front suspension crossmem-
ber.
(9) Remove ICU and the mounting bracket as a
unit from the vehicle.
(10) Remove the 3 bolts (Fig. 21) mounting the
ICU to the mounting bracket. Separate the ICU from
the mounting bracket.
(11) For the procedure on separating and attaching
the CAB to the HCU, refer to DISASSEMBLY.DISASSEMBLY - ICU
(1) Remove the ICU from the vehicle. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - REMOVAL)
(2) Disconnect the pump/motor wiring harness
from the CAB (Fig. 22).
(3) Remove the 4 bolts (Fig. 23) attaching the CAB
to the HCU.
Fig. 20 ICU To Suspension Cradle Mounting Bolts
1 - HCU MOUNTING BRACKET BOLTS
2 - HCU MOUNTING BRACKET BOLT
3 - CAB
4 - HCU MOUNTING BRACKET
5 - HCU
Fig. 21 ICU Mounting Bolts
1 - HCU
2 - HCU MOUNTING BOLTS
3 - HCU MOUNTING BRACKET
Fig. 22 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 23 (TYPICAL) CAB Attaching Bolts
1 - MOUNTING BOLTS
2 - CAB
3 - HCU VALVE BLOCK
RSBRAKES - ABS5 - 105
ICU (INTEGRATED CONTROL UNIT) (Continued)
(4) Remove the CAB from the HCU (Fig. 24).
ASSEMBLY - ICU
(1) Install the CAB (Fig. 24) on the HCU.
(2) Install the 4 bolts mounting the CAB (Fig. 23)
to the HCU. Tighten the CAB mounting bolts to a
torque of 2 N´m (17 in. lbs.).
(3) Plug the pump/motor wiring harness into the
CAB.
(4) Install the ICU in the vehicle and bleed the
base and ABS hydraulic systems. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - INSTALLATION)
INSTALLATION
INSTALLATION - LHD
(1) Place the ICU in its bracket below the master
cylinder. Start the upper mounting bolt to hold it in
place.
(2) Inside the vehicle, install the remaining 2
mounting bolts attaching the ICU to the mounting
bracket (Fig. 16). Tighten all 3 mounting bolts to a
torque of 11 N´m (97 in. lbs.).
(3) Install the dash seal and three mounting
screws (Fig. 15).
(4) If equipped, install the silencer on top of the
dash seal (Fig. 15).
(5) Connect the steering shaft coupling and install
the pinch bolt (Fig. 15). Tighten the pinch bolt to 28
N´m (250 in. lbs.).
(6) Remove the steering wheel holder.
CAUTION: Because of the flexible section in the pri-
mary and secondary brake tubes, the brake tubes
must be held in proper orientation when tightenedand torqued. These tubes must not contact each
other or other vehicle components when installed.
Also, after the brake tubes are installed on the HCU,
ensure all spacer clips are reinstalled on the brake
tubes.
(7) Install the primary and secondary brake tubes
into their correct port locations on the HCU valve
block (Fig. 14). Tighten the tube nuts to a torque of
17 N´m (145 in. lbs.).
CAUTION: When installing the chassis brake tubes
on the HCU valve block, they must be located cor-
rectly in the valve block to ensure proper ABS oper-
ation.
NOTE: The chassis brake tube attachment locations
to the HCU, are marked on the bottom of the CAB.
(8) Install the (4) chassis brake tubes into their
correct port locations on the HCU valve block as
shown (Fig. 14). Tighten the tube nuts to a torque of
17 N´m (145 in. lbs.).
NOTE: Before installing the 24±way connector in
the CAB be sure the seal is properly installed in the
connector.
(9) Install the 24±way connector on the CAB by,
first, positioning the 24±way connector in the socket
of the CAB and carefully pushing it down as far as
possible. Once connector is fully seated by hand into
the CAB socket, push down on connector lock. This
will pull the connector into the socket of the CAB
and lock it in the installed position.
(10) Install any routing clips on the brake tubes.
(11) Remove the brake pedal holder.
(12) Install the speed control servo with its mount-
ing nuts.
(13) Connect the wiring harness to the speed con-
trol servo.
(14) Install the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - INSTALLA-
TION).
(15) Install the screw securing the coolant filler
neck to the battery tray.
(16) Reconnect the vacuum hose connector at the
tank built into the battery tray.
(17) Install the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - INSTALLA-
TION).
(18) Install the battery shield.
(19) Remove the brake pedal holder.
(20) Connect negative cable back on negative post
of the battery.
Fig. 24 (TYPICAL) Remove/Install CAB
1 - CAB
2 - HCU VALVES
3 - HCU VALVE BLOCK
5 - 106 BRAKES - ABSRS
ICU (INTEGRATED CONTROL UNIT) (Continued)
(21) Bleed the Base and ABS brake hydraulic sys-
tems (Refer to 5 - BRAKES - STANDARD PROCE-
DURE).
(22) Road test vehicle to ensure proper operation
of the base and antilock brake systems.
INSTALLATION - RHD
(1) Install the ICU on the mounting bracket (Fig.
21). Install the 3 bolts (Fig. 21) attaching the ICU to
the mounting bracket. Tighten the 3 mounting bolts
to a torque of 11 N´m (97 in. lbs.).
CAUTION: The ICU mounting bracket to front sus-
pension cradle mounting bolts have a unique corro-
sion protection coating and a special aluminum
washer. For this reason, only the original, or origi-
nal equipment Mopar replacement bolts can be
used to mount the ICU bracket to the front suspen-
sion crossmember.
(2) Install the ICU and its mounting bracket as an
assembly on the front suspension crossmember.
Install the 3 bolts attaching the ICU bracket to the
crossmember (Fig. 20). Tighten the 3 mounting bolts
to a torque of 28 N´m (250 in. lbs.).
CAUTION: Because of the flexible section in the pri-
mary and secondary brake tubes, and the brake
tubes between the HCU and the proportioning
valve, the brake tubes must be held in proper ori-
entation when tightened and torqued. These tubes
must not contact each other or other vehicle com-
ponents when installed. Also, after the brake tubes
are installed on the HCU, ensure all spacer clips are
reinstalled on the brake tubes.
CAUTION: When installing the chassis brake tubes
on the HCU valve block, they must be located cor-
rectly in the valve block to ensure proper ABS oper-
ation. Refer to (Fig. 19) for the correct chassis
brake tube locations.
NOTE: The chassis brake tube attachment locations
to the HCU, are marked on the bottom of the ICU
mounting bracket.
(3) Install the 6 chassis brake tubes into their cor-
rect port locations on the HCU valve block as shown
in (Fig. 19). Tighten the tube nuts to a torque of 17
N´m (145 in. lbs.).
NOTE: Before installing the 24-way connector in the
CAB be sure the seal is properly installed in the
connector.(4) Install the 24-way connector (Fig. 17) on the
CAB using the following procedure. Position the
24-way connector in the socket of the CAB and care-
fully push it down as far as possible. When connector
is fully seated by hand into the CAB socket, push in
the connector lock (Fig. 18). This will pull the connec-
tor into the socket of the CAB and lock it in the
installed position.
NOTE: The CAB wiring harness must be clipped to
the ICU mounting bracket. This will ensure the wir-
ing harness is properly routed and does not contact
the brake tubes or the body of the vehicle.
(5) Clip the cab wiring harness (Fig. 17) to the
ICU mounting bracket.
(6) Install the routing clips (Fig. 25) on the brake
tubes.
(7) Lower the vehicle.
(8) Connect negative cable back on negative post of
the battery.
(9) Bleed the base and ABS hydraulic systems.
(Refer to 5 - BRAKES - STANDARD PROCEDURE)
(10) Road test vehicle to ensure proper operation
of the base and antilock brake systems.
Fig. 25 Brake Tube Routing Clips
1 - ROUTING CLIP
2 - HCU
3 - BRAKE TUBES
4 - ROUTING CLIP
RSBRAKES - ABS5 - 107
ICU (INTEGRATED CONTROL UNIT) (Continued)
ENGINE
DIAGNOSIS AND TESTING - ENGINE COOLING
SYSTEM
Establish what driving condition caused the cooling
system complaint. The problem may be caused by an
abnormal load on the system such as the following:
prolonged idle, very high ambient temperature, slight
tail wind at idle, slow traffic speed, traffic jam, high
speed, steep grade.
DRIVING TECHNIQUES
To avoid overheating the cooling system:
(1) Idle with A/C off when temperature gauge is at
end of normal range.
(2) Do not increase engine speed for more air flow
and coolant flow because the electric motor fan sys-
tems are not responsive to engine RPM. The added
cooling from higher coolant flow rate is more than
offset by increased heat rejection (engine heat added
to coolant).
TRAILER TOWING
Consult the owner's manual under Trailer Towing
and do not exceed specified limits.
VISUAL INSPECTION
If the cooling system problem is not caused by a
driving condition, perform a visual inspection to
determine if there was a recent service or accident
repair, including the following:
²Loose/damaged water pump drive belt
²Incorrect cooling system refilling (trapped air or
low level)
²Brakes possibly dragging
²Damaged hoses
²Loose/damaged hose clamps
²Damaged/incorrect engine thermostat
²Damaged cooling fan motor, fan blade and fan
shroud
²Damaged head gasket
²Damaged water pump
²Damaged radiator
²Damaged coolant recovery system
²Damaged heater core
²Open/shorted electrical circuits
If the visual inspection reveals none of the above
as cause for a cooling system complaint, refer to the
following diagnostic charts.
COOLING SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT.
TEMPERATURE GAUGE READING
MAY BE ABOVE NORMAL BUT
NOT HIGH. COOLANT LEVEL MAY
BE HIGH IN COOLANT RESERVE/
OVERFLOW TANK.1. Pressure relief valve in radiator
cap is defective, or was not
properly seated.1. Check condition of radiator cap
and cap seal. (Refer to 7 -
COOLING/ENGINE/RADIATOR
PRESSURE CAP - DIAGNOSIS
AND TESTING) Replace cap as
necessary.
2. Incorrect cap was installed. 2. Replace cap as necessary.
3. Incorrect coolant mixture. 3. Check concentration level of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the ethylene
glycol-to-water ratio as required.
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING)
7 - 14 ENGINERS
PARK ASSIST SYSTEM
The Park Assist System display activates an audi-
ble tone that changes from intermittent to continu-
ous as the final two Light Emitting Diodes (LED's)
are illuminated on one side or both sides of the dis-
play.
The system detection length from the rear of the
vehicle is 0.3 meters to 1.5 meters. This area extends
around the rear side of the vehicle. The system detec-
tion height from the ground is 0.2 meters to about
1.5 meters. The radio mutes when the system acti-
vates its audible tone.
When the driver selects Reverse the system scans
for objects behind the vehicle using four sensors
located in the rear bumper. A warning display above
the rear window provides both visible and audible
warnings indicating the range of the object.
The system is active only when the transmission
gear selector is in reverse for vehicle speeds less than
16 Km/h (10 mph). If the vehicle's Parking/Emer-
gency Brake is applied, the system is deactivated.
The display contains two sets of yellow and red
Light Emitting Diode's (LED's) that the driver can
see as they look over their shoulder while backing
up. Each side of the vehicle has its own warning
LED's. The system provides a visual warning by illu-
minating one or more yellow LED's as the vehicle
gets closer to the object. As the vehicle continues to
approach the object, one red LED is illuminated and
the system emits a series of short beeps. The tone
will remain constant and both red LED's are illumi-
nated once the vehicle is within 12 inches (30.5 cm)
of the object.
The system can be turned ON or OFF through the
Electronic Vehicle Information Center (EVIC) when
the vehicle is in PARK. If the park assist system is
turned OFF, a single chime will sound and the EVIC
will display the following message ªREAR PARK
ASSIST OFFº, when the vehicle is in reverse.
²Ensure that the rear bumper is free of dirt and
debris to keep the system operating properly.
²Jackhammers, large trucks, and other vibrations
could affect the performance of the system.
²Ensure that the parking brake is not applied.
If ªService Park Assist Systemº appears in the
EVIC after making sure the rear bumper is clean,
proceed to diagnose the system using a scan tool and
the appropriate diagnostic information.
WARNING
On vehicles equipped with airbags, disable
the airbag system before attempting any steer-
ing wheel, steering column, or instrument
panel component diagnosis or service. Discon-
nect and isolate the battery negative (ground)
cable, then wait two minutes for the airbag sys-
tem capacitor to discharge before performing
further diagnosis or service. This is the only
sure way to disable the airbag system. Failure
to take the proper precautions could result in
accidental airbag deployment, personal injury,
or death.
DIAGNOSIS AND TESTING - CHIME SYSTEM
Refer to the proper Body Diagnostic Procedures
manual for complete Diagnosis and Testing of the
Chime System.
NO TONE WHEN IGNITION SWITCH IS TURNED ON
AND DRIVER'S SEAT BELT IS NOT BUCKLED.
(1) Using a DRB llltscan tool, actuate chime
(BCM actuates).
(2) Using a voltmeter, check for voltage:
(a) BCM has two battery feeds at pin 1 and pin
5 of the 6±way connector.
(b) Pin 5 of the (BX2) 32 way connector of the
BCM for ignition feed.
(c) Check voltage (PX2) connector, pin 34 for 12v.
(d) If voltage OK, go to step Step 3
(e) If NO voltage repair as necessary. 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 harness
connectors, splices and grounds.
(3) Check drivers seat belt buckle switch input
(from Occupant Restraint Controller (ORC) for a
closed circuit when not buckled. If input not seen,
look for open in wiring or switch. The switch is
grounded when belt is not buckled.
(4) Verify Programmable Communication Interface
(PCI) data bus communication between ORC and
BCM.
8B - 2 CHIME/BUZZERRS
CHIME/BUZZER (Continued)