2002 CHRYSLER VOYAGER brake fluid

ABS TRACTION CONTROL HYDRAULIC CIRCUIT,
SOLENOID VALVE, AND SHUTTLE VALVE
FUNCTION (ABS WITH TRACTION CONTROL)
The hydraulic diagram (Fig. 11) shows the vehicle
in the ABS braking mode. The diagram shows a drive
wheel is spinning and brake pressure is required to
reduce its speed.
²The normally open ASR valve is energized to iso-
late the brake fluid being pumped from the master
cylinder and to isolate the driven wheel.
²The normally open ASR valve bypasses the
pump output back to the master cylinder at a fixed
pressure setting.
²The normally open and normally closed valves
modulate (build/decay) the brake pressure as
required to the spinning wheel.
Fig. 11 Traction Control Hydraulic Circuit
1 - OUTLET VALVE
2 - PUMP PISTON
3 - PUMP MOTOR (ON)
4 - LOW PRESSURE ACCUMULATOR PRESSURE
5 - LOW PRESSURE ACCUMULATOR
6 - NORMALLY CLOSED VALVE (MODULATING)
7 - TO RIGHT FRONT WHEEL (SPINNING)
8 - NORMALLY OPEN VALVE (MODULATING)
9 - NORMALLY OPEN ASR VALVE ON (REGULATING)10 - FROM MASTER CYLINDER
11 - HYDRAULIC SHUTTLE VALVE
12 - CONTROLLED WHEEL PRESSURE
13 - SUCTION VALVE
14 - PUMP INTERSTAGE PRESSURE
15 - NOISE DAMPER CHAMBER
16 - MASTER CYLINDER PRESSURE
17 - PUMP PRESSURE
5 - 98 BRAKES - ABSRS
HYDRAULIC/MECHANICAL (Continued)
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HCU (HYDRAULIC CONTROL
UNIT)
DESCRIPTION
The hydraulic control unit (HCU) is mounted to
the CAB as part of the ICU (Fig. 22). The HCU con-
trols the flow of brake fluid to the brakes using a
series of valves and accumulators. A pump/motor is
mounted on the HCU to supply build pressure to the
brakes during an ABS stop.
The HCU on a vehicle equipped with ABS and
traction control has a valve block housing that is
approximately 1 inch longer on the low pressure fluid
accumulators side than a HCU on a vehicle that is
equipped with only ABS.
For more information, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ICU (INTEGRATED CON-
TROL UNIT) - DESCRIPTION)
OPERATION
For information on the operation of the HCU as a
whole, refer to Hydraulic Circuits And Valve Opera-
tion which can be found elsewhere in this section.
For information on the operation of the components
within the HCU, refer to the following three topics.
VALVES AND SOLENOIDS
The valve block contains four inlet valves and four
outlet valves. The inlet valves are spring-loaded in
the open position and the outlet valves are spring-
loaded in the closed position during normal braking.
The fluid is allowed to flow from the master cylinder
to the wheel brakes.
During an ABS stop, these valves cycle to maintain
the proper slip ratio for each wheel. The inlet valve
closes preventing further pressure increase and the
outlet valve opens to provide a path from the wheel
brake to the HCU accumulators and pump/motor.
This releases (decays) pressure from the wheel brake,
thus releasing the wheel from excessive slippage.
Once the wheel is no longer slipping, the outlet valve
is closed and the inlet valve is opened to reapply
(build) pressure.
On vehicles with traction control, there is an extra
set of valves and solenoids. The ASR valves, mounted
in the HCU valve block, are normally in the open
position and close only when the traction control is
applied.
These isolator valves are used to isolate the rear
(non-driving) wheels of the vehicle from the hydraulicpressure that the HCU pump/motor is sending to the
front (driving) wheels when traction control is being
applied. The rear brakes need to be isolated from the
master cylinder when traction control is being
applied so the rear wheels do not drag. For more
information, refer to Traction Control System in this
section.
BRAKE FLUID ACCUMULATORS
There are two fluid accumulators in the HCU±one
for the primary hydraulic circuit and one for the sec-
ondary hydraulic circuit. Each hydraulic circuit uses
a 5 cc accumulator.
The fluid accumulators temporarily store brake
fluid that is removed from the wheel brakes during
an ABS cycle. This stored fluid is used by the pump/
motor to provide build pressure for the brake hydrau-
lic system. When the antilock stop is complete, the
accumulators are drained by the pump/motor.
On ABS-only vehicles, there is a mini-accumulator
on the secondary hydraulic circuit that protects the
master cylinder seals during an ABS stop, and there
is a noise dampening chamber on the primary circuit.
On ABS with traction control vehicles, there are
two noise dampening chambers in the HCU.
PUMP/MOTOR
There are two pump assemblies in the HCUÐone
for the primary hydraulic circuit and one for the sec-
ondary hydraulic circuit. Both pumps are driven by a
common electric motor. This DC-type motor is inte-
gral to the HCU and is controlled by the CAB.
The pump/motor provides the extra amount of
brake fluid needed during antilock braking. Brake
fluid is released to the accumulators when the outlet
valve is opened during an antilock stop. The pump
mechanism consists of two opposing pistons operated
by an eccentric camshaft. In operation, one piston
draws fluid from the accumulators, and the opposing
piston pumps fluid to the master cylinder circuits.
When the antilock stop is complete, the pump/motor
drains the accumulators.
The CAB may turn on the pump/motor when an
antilock stop is detected. The pump/motor continues
to run during the antilock stop and is turned off after
the stop is complete. Under some conditions, the
pump/motor runs to drain the accumulators during
the next drive-off.
The pump/motor is not a serviceable item; if it
requires replacement, the HCU must be replaced.
RSBRAKES - ABS5-99
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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 a
vehicle 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).
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 - 100 BRAKES - ABSRS
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(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
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 silencer panel under the instru-
ment panel, below the steering column.(16) Remove the pinch bolt and disconnect the
steering shaft coupling.
(17) Remove the two clips securing silencer to dash
seal (Fig. 15).
(18) Remove the three screws securing the dash
seal (Fig. 15).
(19) Remove the 3 bolts attaching the ICU to its
mounting bracket (Fig. 16).
(20) Remove ICU from the vehicle through engine
compartment.
(21) If required, to separating the CAB from the
HCU, (Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-
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
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
RSBRAKES - ABS5 - 101
ICU (INTEGRATED CONTROL UNIT) (Continued)
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STANDARD PROCEDURE
STANDARD PROCEDURE - COOLANT SERVICE
For engine coolant recommended service schedule,
(Refer to LUBRICATION & MAINTENANCE/MAIN-
TENANCE SCHEDULES - DESCRIPTION).
STANDARD PROCEDURE - ADDING
ADDITIONAL COOLANT
The pressure/vent cap should not be removed
from the coolant recovery pressure container
when the engine is hot.When additional coolant is
needed to maintain this level, it should be added to
the coolant recovery pressure container (Fig. 1). Use
only 50/50 mix of ethylene glycol type antifreeze and
distilled water. For the recommeded antifreeze/cool-
ant type (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - DESCRIPTION).
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended. For the
recommeded antifreeze/coolant type (Refer to
LUBRICATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION).
STANDARD PROCEDURE - COOLANT LEVEL
CHECK
NOTE: Do not remove pressure/vent cap for routine
coolant level inspections.
The coolant reserve system provides a quick visual
method for determining the coolant level without
removing the pressure/vent cap.With the engine
cold and not running,simply observe the level of
the coolant in the coolant recovery pressure container
(Fig. 2). The coolant level should be between the MIN
and MAX marks.
STANDARD PROCEDURE - COOLING SYSTEM
FILLING
(1) Remove pressure vent cap from coolant recov-
ery pressure container.
(2) Loosen air bleed screw on the thermostat hous-
ing (Fig. 9).
(3) Slowly fill the cooling through the coolant
recovery pressure container until a steady stream of
coolant comes out of the air bleed.
(4) Tighten the air bleed screw.
Fig. 1 UNDERHOOD FLUID FILL LOCATIONS
1 - COOLANT PRESSURE/VENT CAP
2 - BRAKE MASTER CYLINDER
3 - INTELLIGENT POWER MODULE
4 - BATTERY
5 - COOLANT RECOVERY PRESSURE CONTAINER6 - OIL DIPSTICK
7 - WINDSHIELD SOLVENT RESEVOIR
8 - AIR FILTER HOUSING
9 - ENGINE OIL FILL CAP
7a - 16 ENGINERG
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When replacing a BCM there are three modules
available:
²Base
²Midline
²Highline
The Midline controller is used on vehicles that
have Power Door Locks and the Highline controller is
used for vehicles equipped with a Power Liftgate. If a
vehicle is equipped with the Vehicle Theft Security
System, the Midline/Highline controller becomes a
Premium when the theft feature is enabled.
CAUTION: Do not swap Body Control Modules
between vehicles or body controller's off the shelf.
The BCM has internal diagnostic capability that
assists in diagnosing the system error. When an
OPEN or a SHORT circuit exists, the diagnostic tool
can be used to read the BCM faults. The faults are
very descriptive in identifying the appropriate fea-
ture that has faulted.
The only two faults that the BCM logs that con-
clude the replacement of a BCM are faults;
²# 01 - Internal BCM failure (replace BCM)
²# 1F - J1850 Internal Hardware Failure (replace
BCM)
Otherwise the appropriate diagnostic procedures
for each of the features should be taken when the
BCM logs a fault.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the lower instrument panel silencer.
(3) Remove the knee blocker and reinforcement
(Refer to 23 - BODY/INSTRUMENT PANEL/KNEE
BLOCKER REINFORCEMENT - REMOVAL).
(4) Disconnect the five wire connectors from the
bottom of the Body Control Module (BCM).
(5) Move bulkhead wiring aside.
(6) Remove the screws holding the BCM to the
bulkhead.
(7) Remove the BCM from the mounting bracket.
INSTALLATION
(1) Install the BCM to the mounting bracket.
(2) Install the screws holding the BCM to the
bulkhead.
(3) Connect the five wire connectors to the bottom
of the Body Control Module (BCM).
(4) Install the knee blocker and reinforcement
(Refer to 23 - BODY/INSTRUMENT PANEL/KNEE
BLOCKER REINFORCEMENT - INSTALLATION).
(5) Install the lower instrument panel silencer.
(6) Connect the battery negative cable.
(7) Verify proper operation of BCM and its func-
tions.
CONTROLLER ANTILOCK
BRAKE
DESCRIPTION
The controller antilock brake (CAB) is a micropro-
cessor-based device which monitors the antilock
brake system (ABS) during normal braking and con-
trols it when the vehicle is in an ABS stop. The CAB
is mounted to the HCU as part of the integrated con-
trol unit (ICU) (Fig. 2). The CAB uses a 24-way elec-
trical connector on the vehicle wiring harness. The
power source for the CAB is through the ignition
switch in the RUN or ON position. The CAB is on
the PCI bus.
OPERATION
The primary functions of the controller antilock
brake (CAB) are to:
²Monitor the antilock brake system for proper
operation.
²Detect wheel locking or wheel slipping tenden-
cies by monitoring the speed of all four wheels of the
vehicle.
²Control fluid modulation to the wheel brakes
while the system is in an ABS mode.
²Store diagnostic information.
²Provide communication to the DRBIIItscan tool
while in diagnostic mode.
²Illuminate the amber ABS warning indicator
lamp.
²(With traction control only) Illuminate the TRAC
ON lamp in the message center on the instrument
panel when a traction control event occurs.
Fig. 2 Integrated Control Unit (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
RSELECTRONIC CONTROL MODULES8E-5
BODY CONTROL MODULE (Continued)
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²(with traction control only) Illuminate the TRAC
OFF lamp when the amber ABS warning indicator
lamp illuminates.
The CAB constantly monitors the antilock brake
system for proper operation. If the CAB detects a
fault, it will turn on the amber ABS warning indica-
tor lamp and disable the antilock braking system.
The normal base braking system will remain opera-
tional.
NOTE: If the vehicle is equipped with traction con-
trol, the TRAC OFF lamp will illuminate anytime the
amber ABS warning indicator lamp illuminates.
The CAB continuously monitors the speed of each
wheel through the signals generated by the wheel
speed sensors to determine if any wheel is beginning
to lock. When a wheel locking tendency is detected,
the CAB commands the CAB command coils to actu-
ate. The coils then open and close the valves in the
HCU that modulate brake fluid pressure in some or
all of the hydraulic circuits. The CAB continues to
control pressure in individual hydraulic circuits until
a locking tendency is no longer present.
The CAB contains a self-diagnostic program that
monitors the antilock brake system for system faults.
When a fault is detected, the amber ABS warning
indicator lamp is turned on and the fault diagnostic
trouble code (DTC) is then stored in a diagnostic pro-
gram memory. These DTC's will remain in the CAB
memory even after the ignition has been turned off.
The DTC's can be read and cleared from the CAB
memory by a technician using the DRBIIItscan tool.
If not cleared with a DRBIIItscan tool, the fault
occurrence and DTC will be automatically cleared
from the CAB memory after the identical fault has
not been seen during the next 3,500 miles.
CAB INPUTS
²Wheel speed sensors (four)
²Brake lamp switch
²Ignition switch
²System and pump voltage
²Ground
²Traction control switch (if equipped)
²Diagnostic communication (PCI)
CAB OUTPUTS
²Amber ABS warning indicator lamp actuation
(via BUS)
²Instrument cluster (MIC) communication (PCI)
²Traction control lamps (if equipped)
²Diagnostic communication (PCI, via BUS)
REMOVAL
(1) Disconnect the battery cables.(2) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(3) Disconnect the vacuum hose connector at the
tank built into the battery tray.
(4) Remove the screw securing the coolant filler
neck to the battery tray.
(5) Remove the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - REMOVAL).
(6) Pull up on the CAB connector lock and discon-
nect the 24±way electrical connector (Fig. 3).
(7) Disconnect the pump/motor connector from the
CAB.
(8) Remove the screws securing the CAB to the
HCU (Fig. 4)
(9) Pull CAB straight forward off HCU.
INSTALLATION
(1) Slide the CAB onto the HCU (Fig. 4).
(2) Install screws securing the CAB to the HCU
(Fig. 4) Tighten the mounting screws to 2 N´m (17 in
lbs).
(3) Reconnect the 24±way wiring connector and
the pump/motor wiring connector. (Fig. 3)
(4) Install the battery tray (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/TRAY - INSTALLATION).
(5) Install the screw securing the coolant filler
neck to the battery tray.
(6) Reconnect the vacuum hose to the coolant tank
built into the battery tray.
(7) Install the battery (Refer to 8 - ELECTRICAL/
BATTERY SYSTEM/BATTERY - INSTALLATION).
(8) Reconnect the battery cables.
Fig. 3 CAB Connector Lock
1 - CONNECTOR LOCK
2 - CAB
8E - 6 ELECTRONIC CONTROL MODULESRS
CONTROLLER ANTILOCK BRAKE (Continued)
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²Back-Up switch
²Brake Fluid Level
²B+ Connection Detection
²Engine Crank Signal (Diesel Engine Vehicles)
²Horn Input
²Ignition Switch Start Only
²Ignition Switch Run and Start Only
²Stop Lamp Sense
²Washer Fluid Level
²Windshield Wiper Park
DIAGNOSIS AND TESTING - FRONT CONTROL
MODULE
The Front Control Module (FCM) is a printed cir-
cuit board based module with a on-board micro-pro-
cessor. The FCM interfaces with other electronic
modules in the vehicle via the Programmable Com-
munications Interface (PCI) data bus. In order to
obtain conclusive testing the PCI data bus and all of
the electronic modules that provide inputs to, or
receive outputs from the FCM must be checked. All
PCI communication faults must be resolved prior to
further diagnosing any front control module related
issues.
The FCM was designed to be diagnosed with an
appropriate diagnostic scan tool, such as the DRB
IIIt. The most reliable, efficient, and accurate means
to diagnose the front control module requires the use
of a DRB IIItscan tool and the proper Body Diag-
nostic Procedures manual.
Before any testing of the FCM is attempted, the
battery should be fully charged and all wire harness
and ground connections inspected around the affected
areas on the vehicle.
REMOVAL
(1) Disconnect the positive and negative battery
cables from the battery.
(2) Remove the battery from the vehicle. Refer to
the procedure in Battery Systems.
(3) Using a long flat-bladed screwdriver, gently
twist the Integrated Power Module (IPM) retaining
clip outboard to free the IPM from its mounting
bracket (Fig. 6). Rotate IPM upward to access the
Front Control Module (FCM) retaining screws.
(4) Remove the front control module retaining
screws.
(5) Using both hands, pull the FCM straight from
the IPM assembly to disconnect the 49-way electrical
connector (Fig. 7) and remove the front control mod-
ule from the vehicle.
INSTALLATION
NOTE: Front Control Module must be programmed
to the correct radio EQ curve using the DRB IIIT.This will ensure that the audio system is operating
correctly.
(1) Install the Front Control Module (FCM) in the
Integrated Power Module (IPM) assembly by pushing
the 49-way electrical connector straight in.
(2) Install the FCM retaining screws. Torque the
screws to 1 N´m (7 in. lbs).
(3) Rotate the IPM assembly downward to secure
in mounting bracket.
Fig. 6 REMOVING INTELLIGENT POWER MODULE
Fig. 7 FRONT CONTROL MODULE
1 - FRONT CONTROL MODULE
8E - 8 ELECTRONIC CONTROL MODULESRS
FRONT CONTROL MODULE (Continued)
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