brake light DODGE RAM 1500 1998 2.G Owner's Manual

INSTALLATION
(1) Install support plate on axle flange (Fig. 66).
Tighten attaching bolts to 115 N´m (85 ft. lbs.).
(2) Install parking brake cable in the brake lever.
(3) Install the park brake shoes (Refer to 5 -
BRAKES/PARKING BRAKE/SHOES - INSTALLA-
TION). (Fig. 66).
(4) Install axle shaft, (Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE - 9 1/4/AXLE
SHAFTS - INSTALLATION).
(5) Adjust brake shoes to drum with brake gauge
(Refer to 5 - BRAKES/PARKING BRAKE/SHOES -
ADJUSTMENTS).
(6) Install the rotor (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTORS - INSTALLA-
TION).
(7) Install the caliper adapter (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPER ADAPTER - INSTALLATION).
(8) Install the caliper (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION).
(9) Install the wheel and tire assembly (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
PARKING BRAKE
DESCRIPTION
The parking brakes are operated by a system of
cables and levers attached to a primary and second-
ary shoe positioned within the drum section of the
rotor.
The drum-in-hat design utilizes an independent set
of shoes to park the vehicle (Fig. 67).
OPERATION
To apply the parking brake the pedal is depressed.
This creates tension in the cable which pulls forward
on the park brake lever. The lever pushes the park
brake shoes outward and into contact with the drum
section of the rotor. The contact of shoe to rotor parks
the vehicle.
A torsion locking mechanism is used to hold the
pedal in an applied position. Parking brake release is
accomplished by the hand release.
A parking brake switch is mounted on the parking
brake lever and is actuated by movement of the
lever. The switch, which is in circuit with the red
warning light in the dash, will illuminate the warn-
ing light whenever the parking brake is applied.
Parking brake adjustment is controlled by a cable
tensioner mechanism. The cable tensioner, once
adjusted at the factory, should not need further
adjustment under normal circumstances. Adjustment
may be required if a new tensioner, or cables are
installed, or disconnected.
CABLES
REMOVAL
REMOVAL - FRONT PARKING BRAKE CABLE
(1) Raise and support vehicle.
(2) Lockout the parking brake cable (Fig. 69).
(3) Loosen adjusting nut to create slack in front
cable.
(4) Remove the front cable from the cable connec-
tor.
Fig. 66 SUPPORT PLATE WITH BRAKES MOUNTED
1 - SUPPORT PLATE
2 - MOUNTING NUTS
Fig. 67 SUPPORT PLATE WITH BRAKES MOUNTED
1 - SUPPORT PLATE
2 - MOUNTING NUTS
5 - 36 BRAKES - BASEDR
SUPPORT PLATE (Continued)

INSTALLATION - LEFT REAR CABLE
(1) Install the brake cable to the brake lever (Fig.
72).
(2) Install the brake cable to the frame bracket.
(3) Install the left brake cable to the equalizer.
(4) Adjust the brake cable at the equalizer and
adjuster nut.
SHOES
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the tire and wheel assembly.
(3) Remove the disc brake caliper,(Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPERS - REMOVAL).
(4) Remove the disc brake rotor, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ROTORS -
REMOVAL).
(5) Lockout the parking brake cable (Fig. 74).
(6) Disengage the park brake cable from behind
the rotor assembly to allow easier disassembly of the
park brake shoes (Fig. 75).
(7) Remove the axleshaft (Fig. 76) (Refer to 3 -
DIFFERENTIAL & DRIVELINE/REAR AXLE - 9 1/4/
AXLE SHAFTS - REMOVAL).
(8) Disassemble the rear park brake shoes (Fig.
67).
CLEANING - REAR DRUM IN HAT BRAKE
Clean the individual brake components, including
the support plate exterior, with a water dampened
cloth or with brake cleaner. Do not use any other
cleaning agents. Remove light rust and scale fromthe brake shoe contact pads on the support plate
with fine sandpaper.
INSPECTION - REAR DRUM IN HAT BRAKE
As a general rule, riveted brake shoes should be
replaced when worn to within 0.78 mm (1/32 in.) of
the rivet heads. Bonded lining should be replaced
when worn to a thickness of 1.6 mm (1/16 in.).
Examine the lining contact pattern to determine if
the shoes are bent or the drum is tapered. The lining
should exhibit contact across its entire width. Shoes
exhibiting contact only on one side should be
replaced and the drum checked for runout or taper
(Fig. 77).
Fig. 73 PARKING BRAKE CABLE
1 - SUPPORT PLAT
2 - CABLE
3 - LEVER
Fig. 74 LOCK OUT PARKING CABLE
1 - LOCKING PLIERS
2 - PARKING BRAKE CABLE
Fig. 75 DISENGAGEMENT OF CABLE
1 - LEVER
2 - CABLE END
DRBRAKES - BASE 5 - 39
CABLES (Continued)

Inspect the adjuster screw assembly. Replace the
assembly if the star wheel or threads are damaged,
or the components are severely rusted or corroded
(Fig. 77).
Discard the brake springs and retainer components
if worn, distorted or collapsed. Also replace the
springs if a brake drag condition had occurred. Over-
heating will distort and weaken the springs.
Inspect the brake shoe contact pads on the support
plate, replace the support plate if any of the pads are
worn or rusted through. Also replace the plate if it is
bent or distorted (Fig. 77).
INSTALLATION
NOTE: On a new vehicle or after parking brake lin-
ing replacement, it is recommended that the park-
ing brake system be conditioned prior to use. This
is done by making one stop from 25 mph on dry
pavement or concrete using light to moderate force
on the parking brake foot pedal.
(1) Reassemble the rear park brake shoes (Fig. 67)
or (Fig. 78).
(2) Install the axleshaft (Fig. 76) (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/REAR AXLE - 9 1/4/
AXLE SHAFTS - INSTALLATION) or (Refer to 3 -
DIFFERENTIAL & DRIVELINE/REAR AXLE - 11
1/2 AA/10 1/2 AA/AXLE SHAFTS - INSTALLATION).
(3) Install the park brake cable to the lever behind
the support plate.
(4) Unlock the park brake cable.
(5) Install the disc brake rotor (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ROTORS -
INSTALLATION).(6) Install the disc brake caliper (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPERS - INSTALLATION).
(7) Adjust the rear brake shoes (Refer to 5 -
BRAKES/PARKING BRAKE/SHOES - ADJUST-
MENTS).
Fig. 76 AXLE SHAFT
1 - AXLE SHAFT
2 - SUPPORT PLATE
3 - CALIPER
4 - PARK BRAKE SHOE ASSEMBLY
Fig. 77 PARK BRAKE SHOES
1 - SUPPORT PLATE
2 - SHOES
3 - RETURN SPRINGS
4 - RETAINER CLIPS
5 - ADJUSTER
Fig. 78 SHOE ASSEMBLY
1 - Park Brake Shoes
2 - Hold Downs
3 - Return Springs
5 - 40 BRAKES - BASEDR
SHOES (Continued)

(12) Rotate rotor to verify that the park brake
shoes are not dragging on the brake drum. If park
brake shoes are dragging, remove rotor and back off
star wheel adjuster one notch and recheck for brake
shoe drag against drum. Continue with the previous
step until brake shoes are not dragging on brake
drum.
(13) Install disc brake caliper on caliper adapter
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
DISC BRAKE CALIPERS - INSTALLATION).
(14) Install wheel and tire.
(15) Tighten the wheel mounting nuts in the
proper sequence until all nuts are torqued to half the
specified torque. Then repeat the tightening sequence
to the full specified torque of 180 N´m (135 ft. lbs.)
1500 & 2500 Series or 195 N´m (145 ft. lbs.) 3500
Series.
(16) Lower vehicle.
(17) Apply and release the park brake pedal one
time. This will seat and correctly adjust the park
brake cables.
CAUTION: Before moving vehicle, pump brake
pedal several times to ensure the vehicle has a firm
enough pedal to stop the vehicle.
NOTE: On a new vehicle or after parking brake lin-
ing replacement, it is recommended that the park-
ing brake system be conditioned prior to use. This
is done by making one stop from 25 mph on dry
pavement or concrete using light to moderate force
on the parking brake foot pedal.
(18) Road test the vehicle to ensure proper func-
tion of the vehicle's brake system.
ADJUSTMENT - WITH ADJUSTING TOOL
Adjustment can be made with a standard brake
gauge or with adjusting tool. Adjustment is per-
formed with the complete brake assembly installed
on the backing plate.
(1) Be sure parking brake lever is fully released.
(2) Raise vehicle so rear wheels can be rotated
freely.
(3) Remove plug from each access hole in brake
support plates.
(4) Loosen parking brake cable adjustment nut
until there is slack in front cable.
(5) Insert adjusting tool through support plate
access hole and engage tool in teeth of adjusting
screw star wheel (Fig. 82).
(6) Rotate adjuster screw star wheel (move tool
handle upward) until slight drag can be felt when
wheel is rotated.
(7) Back off adjuster screw star wheel until brake
drag is eliminated.(8) Repeat adjustment at opposite wheel. Be sure
adjustment is equal at both wheels.
(9) Install support plate access hole plugs.
(10) Adjust parking brake cable and lower vehicle.
(11) Depress park brake pedal and make sure park
brakes hold the vehicle staionary.
(12) Release park brake pedal.
PEDAL
REMOVAL
(1) Release the parking brake.
(2) Raise the vehicle.
(3) Loosen the cable tensioner nut at the equalizer
to create slack in the front cable.
(4) Lower the vehicle.
(5) Remove the knee bolster, (Refer to 23 - BODY/
INSTRUMENT PANEL/STEERING COLUMN
OPENING COVER - REMOVAL).
(6) Disconnect the brake lamp wire from the
switch on the pedal assembly.
(7) Roll the carpet back, loosen the front cable
grommet from the floorpan and the cable retainer.
(8) Disengage the release rod (Fig. 83) from the
arm on the pedal assembly.
(9) Remove the bolts/nuts from the pedal assembly
and remove the assembly.
INSTALLATION
(1) Position the replacement pedal assembly on the
dash and cowl.
Fig. 82 Brake Adjustment
1 - STAR WHEEL
2 - LEVER
3 - BRAKE SHOE WEB
4 - SCREWDRIVER
5 - ADJUSTING TOOL
6 - ADJUSTER SPRING
5 - 42 BRAKES - BASEDR
SHOES (Continued)

BRAKES - ABS
TABLE OF CONTENTS
page page
BRAKES - ABS
DESCRIPTION.........................45
OPERATION...........................45
STANDARD PROCEDURE - ABS BRAKE
BLEEDING...........................46
SPECIFICATIONS
TORQUE CHART......................46
FRONT WHEEL SPEED SENSOR
DESCRIPTION.........................47
OPERATION...........................47
REMOVAL.............................48
INSTALLATION.........................48
REAR WHEEL SPEED SENSOR
DIAGNOSIS AND TESTING - REAR WHEEL
ANTILOCK...........................48
REMOVAL.............................48
INSTALLATION.........................48TONE WHEEL
DIAGNOSIS AND TESTING - REAR WHEEL
SPEED SENSOR......................49
HYDRAULIC/MECHANICAL
DESCRIPTION - ELECTRONIC VARIABLE
BRAKE PROPORTIONING...............49
OPERATION - ELECTRONIC VARIABLE
BRAKE PROPORTIONING...............49
HCU (HYDRAULIC CONTROL UNIT)
DESCRIPTION.........................49
OPERATION...........................49
REMOVAL.............................50
INSTALLATION.........................50
R WA L VA LV E
DESCRIPTION.........................50
OPERATION...........................50
REMOVAL.............................51
INSTALLATION.........................51
BRAKES - ABS
DESCRIPTION
The antilock brake system (ABS) is an electroni-
cally operated, three channel brake control system.
The vehicle has Electronic Variable Brake Propor-
tioning (EVBP) designed into the system which elim-
inates the combination/proportioning valve.
The system is designed to prevent wheel lockup
and maintain steering control during braking. Pre-
venting lockup is accomplished by modulating fluid
pressure to the wheel brake units.
The hydraulic system is a three channel design.
The front wheel brakes are controlled individually
and the rear wheel brakes in tandem. The ABS elec-
trical system is separate from other electrical circuits
in the vehicle. A specially programmed controller
antilock brake unit operates the system components.
ABS system major components include:
²Controller Antilock Brakes (CAB)
²Hydraulic Control Unit (HCU)
²Wheel Speed Sensors (WSS)
²ABS Warning Light
OPERATION
Battery voltage is supplied to the CAB. The CAB
performs a system initialization procedure at start
up. A check of the ABS motor is performed at 15miles per hour. Initialization consists of a static and
dynamic self check of system electrical components.
The static and dynamic checks occurs at ignition
start up. During the dynamic check, the CAB briefly
cycles solenoids to verify operation. An audible noise
may be heard during this self check. This noise
should be considered normal. The ABS motor and
pump are then checked at a speed of 15 mile per
hour.
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.
The CAB monitors wheel speed sensor inputs con-
tinuously while the vehicle is in motion. However,
the CAB will not activate any ABS components as
long as sensor inputs indicate normal braking.
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.
The purpose of the antilock system is to prevent
wheel lockup. Preventing lockup helps maintain vehi-
cle braking action and steering control.
The antilock CAB activates the system whenever
sensor signals indicate periods of wheel slip.
The antilock system prevents lockup during a
wheel slip condition by modulating fluid apply pres-
sure to the wheel brake units.
DRBRAKES - ABS 5 - 45

PRESSURE INCREASE
The inlet valve is open and the outlet valve is
closed during the pressure increase cycle. The pres-
sure increase cycle is used to reapply thew brakes.
This cycle controls re-application of fluid apply pres-
sure.
REMOVAL
(1) Install a prop rod on the brake pedal to keep
pressure on the brake system.
(2) Disconnect the battery cables from the battery.
(3) Remove the battery.
(4) Disconnect the two electrical harness connec-
tors (Fig. 5).
(5) Remove the five brake lines from the HCU
(Fig. 5).
(6) Remove HCU/CAB mounting bolts and remove
the HCU/CAB (Fig. 5).
INSTALLATION
NOTE: If the CAB is being replaced with a new CAB
is must be reprogrammed with the use of a DRB III.
(1) Install HCU/CAB on the mounts and Tighten
the bolts to 15N´m (11 ft. lbs.) (Fig. 5).
(2) Install the five brake lines to the HCU and
tighten to 19 N´m (170 in. lbs.) (Fig. 5).
(3) Install the two electrical harness connectors to
the HCU/CAB and push down on the release to
secure the connectors.
(4) Install the battery.
(5) Install the battery cables to the battery.
(6) Remove the prop rod on the brake pedal.
(7) Bleed ABS brake system (Refer to 5 - BRAKES
- STANDARD PROCEDURE).
RWAL VALVE
DESCRIPTION
Rear Wheel Antilock (RWAL) brake system is stan-
dard equipment on 1500 series vehicles. The RWAL
brake system is designed to prevent rear wheel
lock-up on virtually all types of road surfaces. RWAL
braking is desirable because a vehicle which is
stopped without locking the rear wheels will retain
directional stability. This allows the driver to retain
greater control of the vehicle during braking.
The valve is located on the drivers side inner
fender under the hood. The valve modulates hydrau-
lic pressure to the rear brakes.
The RWAL components include:
²RWAL Valve
²Controller Antilock brake (CAB)
²Rear Wheel Speed Sensor (WSS)
OPERATION
When the brakes are applied, hydraulic fluid is
routed from the master cylinder's secondary circuit to
the RWAL valve. From there hydraulic fluid is routed
to the rear brakes. The Controller Antilock Brake
(CAB) contains an Electronic Variable Brake Propor-
tioning (EVBP) control algorithm, which proportions
the applied braking force to the rear wheels during
braking. The EVBP function of the RWAL system
takes the place of a conventional hydraulic propor-
tioning valve. The CAB monitors the rear wheel
speed through the rear wheel speed sensor and cal-
culates an estimated vehicle deceleration. When an
established deceleration threshold is exceeded, an
isolation valve is closed to hold the applied brake
pressure to the rear brakes constant. Upon further
increases in the estimated vehicle deceleration, the
isolation valve is selectively opened to increase rear
brake pressure in proportion to the front brake pres-
sure. If impending rear wheel lock-up is sensed, the
CAB signals the RWAL valve to modulate hydraulic
brake pressure to the rear wheels to prevent lock-up.
NORMAL BRAKING Since the RWAL valve also
performs the EVBP or proportioning function, vehicle
deceleration under normal braking may be sufficient
to trigger the EVBP function of the RWAL system
without full RWAL activity as would normally occur
during an impending rear wheel lock-up. As previ-
ously mentioned, the isolation valve is selectively
closed and opened to increase rear brake pressure in
proportion to the front brake pressure under EVBP
control. Slight brake pedal pulsations may be noticed
as the isolation valve is opened.
Fig. 5 HYDRAULIC CONTROL UNIT
1 - HYDRAULIC CONTROL UNIT
2 - MOUNTING BOLTS
5 - 50 BRAKES - ABSDR
HCU (HYDRAULIC CONTROL UNIT) (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)1. Radiator and/or A/C condenser
air flow obstructed.1. Remove obstruction and/or clean.
2. Electronically controlled viscous
fan drive not working.2. Check viscous fan drive (Refer to
7 - COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
3. Air seals around radiator
damaged or missing.3. Inspect air seals, repair or
replace as necessary.
INADEQUATE HEATER
PERFORMANCE. GAUGE MAY OR
MAY NOT READ LOW.1. Heavy duty cooling system, and
cooler ambient temperatures.1. None. Normal condition.
2. Obstruction in heater hoses. 2. Remove hoses, remove
obstruction.
3. Electronically controlled viscous
fan stuck on.Check viscous fan drive. (Refer to 7
- COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
4. Water pump damaged. 4. Replace water pump.
HEAT ODOR 1. Damaged or missing drive line
heat shields.1. Repair or replace damaged or
missing heat shields.
2. Electronically controlled viscous
fan drive damaged.2. Check viscous fan drive. (Refer
to 7 - COOLING/ENGINE/FAN
DRIVE VISCOUS CLUTCH -
DIAGNOSIS AND TESTING)
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED OR STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.
²Increasing engine speed for more air flow is rec-
ommended.
TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect the cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
²Service to electrically controlled viscous fan
clutch
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, refer to COOLING SYSTEM DIAGNOSIS
CHART BELOW.
These charts are to be used as a quick-reference
only. Refer to COOLING SYSTEM DIAGNOSIS
CHART
7 - 10 COOLINGDR
COOLING (Continued)

Engine Control Module (ECM) over the PCI data bus
to illuminate the check gauges indicator for a coolant
temperature high condition.
²Fasten Seat Belt Warning- The instrument
cluster chime tone generator will generate repetitive
chimes at a slow rate each time the ignition switch is
turned to the On or Start positions to announce that
the hard wired inputs from the seat belt switch and
the ignition switch indicate that the driver side front
seat belt is not fastened. The chimes will continue to
sound for a duration of about six seconds, until the
driver side front seat belt is fastened, or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Head/Park Lamps-On Warning- The instru-
ment cluster chime tone generator will generate
repetitive chimes at a slow rate to announce that the
hard wired inputs from the driver door ajar switch,
the ignition switch, and the exterior lighting circuitry
of the headlamp switch indicate that the exterior
lamps are turned On with the driver door opened
and the ignition switch in the Off position. The
chimes will continue to sound until the exterior
lamps are turned Off, the driver door is closed, or the
ignition switch is turned to the On position, or the
battery protection time-out expires, whichever occurs
first.
²Key-In-Ignition Warning- The instrument
cluster chime tone generator will generate repetitive
chimes at a slow rate to announce that the hard
wired inputs from the driver door ajar switch, the
ignition switch, and the key-in ignition circuitry of
the ignition switch indicate that the key is in the
ignition lock cylinder with the driver door opened
and the ignition switch in the Off position. The
chimes will continue to sound until the key is
removed from the ignition lock cylinder, the driver
door is closed, or the ignition switch is turned to the
On position, whichever occurs first.
²Low Fuel Warning- The instrument cluster
chime tone generator will generate one chime tone
when the low fuel indicator is illuminated by the
instrument cluster. The instrument cluster uses a
percent tank full message input received from the
PCM over the PCI data bus indicating that there is
less than about one-eighth tank of fuel remaining to
illuminate the low fuel indicator. This chime feature
will only occur once in an ignition cycle.
²Low Oil Pressure Warning (Diesel Engine
Only)- The instrument cluster chime tone generator
will generate repetitive chimes at a fast rate when
the check gauges indicator is illuminated for a low oil
pressure condition. The instrument cluster uses
engine speed and oil pressure message inputs
received from the diesel Engine Control Module
(ECM) over the PCI data bus indicating that theengine is running and that the oil pressure is low to
illuminate the check gauges indicator. The chimes
will continue to sound for five seconds, until the
engine oil pressure message indicates that the oil
pressure is not low, or until the engine speed mes-
sage indicates that the engine is not running, which-
ever occurs first. This chime tone will only occur once
in an ignition cycle.
²Low Wash Warning- The instrument cluster
chime tone generator will generate one chime tone
when the low washer fluid indicator is illuminated by
the instrument cluster. The instrument cluster uses a
message input received from the Front Control Mod-
ule (FCM) over the PCI data bus indicating that
washer fluid level is low within the washer reservoir.
This chime feature will only occur once in an ignition
cycle.
²Overspeed Warning- The instrument cluster
chime tone generator will generate one chime tone to
announce that a vehicle speed message input
received from the PCM over the PCI data bus indi-
cates that the vehicle speed is above a pre-programed
limit.
²Park Brake Reminder- The instrument clus-
ter chime tone generator will generate ten repetitive
chimes at a slow rate to announce that the hard
wired input from the park brake switch and a vehicle
speed message input received from the PCM over the
PCI data bus indicates that the park brake is applied
and the vehicle is moving. This chime feature will
repeat each time the input conditions are met.
²Sentry Key Immobilizer System ªCustomer
Learnº Mode Announcement- This chime feature
is only active on vehicles equipped with the optional
Sentry Key Immobilizer System (SKIS) and sold in
markets where the optional ªCustomer Learnº pro-
gramming feature is available. The instrument clus-
ter chime tone generator will generate one chime to
announce that a status message input received from
the Sentry Key Immobilizer Module (SKIM) over the
PCI data bus indicates that the SKIS is in the ªCus-
tomer Learnº mode, which is used for programming
additional sentry key transponders.
²Transmission Temperature High Warning
(Automatic Transmission only)- The instrument
cluster chime tone generator will generate repetitive
chimes at a slow rate when the transmission temper-
ature indicator is illuminated for a high or critical
transmission fluid temperature condition. The instru-
ment cluster uses transmission temperature message
inputs received from the Transmission Control Mod-
ule (TCM) over the PCI data bus to illuminate the
indicator for a transmission temperature high condi-
tion.
²Turn Signal On Warning- The instrument
cluster chime tone generator will generate repetitive
8B - 2 CHIME/BUZZERDR
CHIME WARNING SYSTEM (Continued)

The PCI data bus can be monitored using the
DRBIIItscan tool. It is possible, however, for the bus
to pass all DRBIIIttests and still be faulty if the
voltage parameters are all within the specified range
and false messages are being sent.
CONTROLLER ANTILOCK
BRAKE
DESCRIPTION
The Controler Antilock Brake (CAB) is mounted to
the Hydraulic Control Unit (HCU) and operates the
ABS system (Fig. 1).
OPERATION
The CAB voltage source is through the ignition
switch in the RUN position. The CAB contains a self
check program that illuminates the ABS warning
light when a system fault is detected. Faults are
stored in a diagnostic program memory and are
accessible with the DRB III scan tool. ABS faults
remain in memory until cleared, or until after the
vehicle is started approximately 50 times. Stored
faults arenoterased if the battery is disconnected.
NOTE: If the CAB is being replaced with a new CAB
is must be reprogrammed with the use of a DRB III.
REMOVAL
(1) Remove the negative battery cable from the
battery.
(2) Pull up on the CAB harness connector release
and remove connector.
(3) Remove the CAB mounting bolts.
(4) Remove the pump connector from the CAB.
(5) Remove the CAB from the HCU.
INSTALLATION
NOTE: If the CAB is being replaced with a new CAB
is must be reprogrammed with the use of a DRB III.
(1) Install CAB to the HCU.
(2) Install the pump connector to the CAB.
(3) Install mounting bolts. Tighten to 2 N´m (16 in.
lbs.).
(4) Install the wiring harness connector to the
CAB and push down on the release to secure the con-
nector.
(5) Install negative battery cable to the battery.
DATA LINK CONNECTOR
DESCRIPTION - DATA LINK CONNECTOR
The Data Link Connector (DLC) is located at the
lower edge of the instrument panel near the steering
column.
OPERATION - DATA LINK CONNECTOR
The 16±way data link connector (diagnostic scan
tool connector) links the Diagnostic Readout Box
(DRB) scan tool or the Mopar Diagnostic System
(MDS) with the Powertrain Control Module (PCM).
ENGINE CONTROL MODULE
DESCRIPTION - ECM
The engine control module (ECM) for the 5.9L Die-
sel engine is bolted to the left side of the engine
below the intake manifold.
OPERATION - ECM
The main function of the Engine Control Module
(ECM) is to electrically control the fuel system. The
Powertrain Control Module (PCM)does notcontrol
the fuel system.
The ECM can adapt its programming to meet
changing operating conditions.If the ECM has
been replaced, flashed or re-calibrated, the
ECM must learn the Accelerator Pedal Position
Sensor (APPS) idle voltage. Failure to learn
this voltage may result in unnecessary diagnos-
tic trouble codes. Refer to ECM Removal/Instal-
lation for learning procedures.
The ECM receives input signals from various
switches and sensors. Based on these inputs, the
ECM regulates various engine and vehicle operations
through different system components. These compo-
nents are referred to asECM Outputs.The sensors
and switches that provide inputs to the ECM are
consideredECM Inputs.
Fig. 1 HYDRAULIC CONTROL UNIT
1 - HYDRAULIC CONTROL UNIT
2 - MOUNTING BOLTS
DRELECTRONIC CONTROL MODULES 8E - 3
COMMUNICATION (Continued)

Sandwiched between the rear cover and the lens,
hood and mask unit is the cluster housing. The
molded plastic cluster housing serves as the carrier
for the cluster circuit board and circuitry, the cluster
connector receptacles, the RKE interface connector,
the gauges, a Light Emitting Diode (LED) for each
cluster indicator, two VFD units, an audible tone
generator, the cluster overlay, the gauge pointers, the
odometer/trip odometer switch and the switch button.
The cluster overlay is a laminated plastic unit. The
dark, visible, outer surface of the overlay is marked
with all of the gauge dial faces and graduations, but
this layer is also translucent. The darkness of this
outer layer prevents the cluster from appearing clut-
tered or busy by concealing the cluster indicators
that are not illuminated, while the translucence of
this layer allows those indicators and icons that are
illuminated to be readily visible. The underlying
layer of the overlay is opaque and allows light from
the LED for each of the various indicators and the
incandescent illumination lamps behind it to be visi-
ble through the outer layer of the overlay only
through predetermined stencil-like cutouts. A rectan-
gular opening in the overlay at the base of both the
speedometer and tachometer dial faces has a smoked
clear lens through which the illuminated VFD units
can be viewed.
Several versions of the EMIC module are offered
on this model. These versions accommodate all of the
variations of optional equipment and regulatory
requirements for the various markets in which the
vehicle will be offered. The microprocessor-based
EMIC utilizes integrated circuitry and information
carried on the Programmable Communications Inter-
face (PCI) data bus network along with several hard
wired analog and multiplexed inputs to monitor sen-
sors and switches throughout the vehicle. In response
to those inputs, the internal circuitry and program-
ming of the EMIC allow it to control and integrate
many electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the PCI data bus. (Refer
to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/COMMUNICATION - DESCRIPTION -
PCI BUS).
Besides typical instrument cluster gauge and indi-
cator support, the electronic functions and features
that the EMIC supports or controls include the fol-
lowing:
²Audible Warnings- The EMIC electronic cir-
cuit board is equipped with an audible tone generator
and programming that allows it to provide various
audible alerts to the vehicle operator, including
chime tones and beep tones. An electromechanical
relay is also soldered onto the circuit board to pro-duce audible clicks that emulate the sound of a con-
ventional turn signal or hazard warning flasher.
(Refer to 8 - ELECTRICAL/CHIME/BUZZER -
DESCRIPTION).
²Brake Lamp Control- The EMIC provides
electronic brake lamp request messages to the Front
Control Module (FCM) located on the Integrated
Power Module (IPM) for brake lamp control, exclud-
ing control of the Center High Mounted Stop Lamp
(CHMSL), which remains controlled by a direct hard
wired output of the brake lamp switch.
²Brake Transmission Shift Interlock Control
- The EMIC monitors inputs from the brake lamp
switch, ignition switch, and the Transmission Range
Sensor (TRS), then controls a high-side driver output
to operate the Brake Transmission Shift Interlock
(BTSI) solenoid that locks and unlocks the automatic
transmission gearshift selector lever on the steering
column.
²Cargo Lamp Control- The EMIC provides
direct control of cargo lamp operation with a load
shedding (battery saver) feature which will automat-
ically turn off the cargo lamp if it remains on after a
timed interval.
²Central Locking- The EMIC provides support
for the central locking feature of the power lock sys-
tem. This feature will lock or unlock all doors based
upon the input from the door cylinder lock switch.
Door cylinder lock switches are used only on models
equipped with the optional Vehicle Theft Security
System (VTSS).
²Door Lock Inhibit- The EMIC inhibits locking
of the doors with the power lock switch when the key
is in the ignition switch and the driver side front
door is ajar. However, operation of the door locks is
not inhibited under the same conditions when the
Lock button of the optional RKE transmitter is
depressed.
²Enhanced Accident Response- The EMIC
monitors an input from the Airbag Control Module
(ACM) and, following an airbag deployment, will
immediately disable the power lock output, unlock all
doors by activating the power unlock output, then
enables the power lock output. This feature, like all
other enhanced accident response features, is depen-
dent upon a functional vehicle electrical system fol-
lowing the vehicle impact event.
²Exterior Lighting Control- The EMIC pro-
vides electronic head lamp and/or park lamp request
messages to the Front Control Module (FCM) located
on the Integrated Power Module (IPM) for the appro-
priate exterior lamp control of standard head and
park lamps, as well as optional front fog lamps. This
includes support for headlamp beam selection and
the optical horn feature, also known as flash-to-pass.
DRINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)