POWER STEERING DODGE RAM 2003 Service Workshop Manual

HEADLAMP SWITCH
DESCRIPTION
The multiplexed headlamp switch is located on the
instrument panel. The headlamp switch controls the
parking lamps, fog lamps and the headlamps. A sep-
arate switch in the module controls the interior
lamps and instrument cluster illumination. This
switch also contains a rheostat for controlling the
illumination level of the cluster lamps.
OPERATION
The multiplexed headlamp switch has an off, park-
ing lamp, fog lamp and a headlamp on position. High
beams are controlled by the multiplexed multifunc-
tion switch on the steering column. The fog lamps
are illuminated by pulling back on the headlamp
switch knob when in the parking lamp or headlamp
ON position.The headlamp switch cannot be
repaired. It must be replaced.
The Instrument Cluster monitors the headlamp
and multifunction switch operation. When the head-
lamp switch is rotated to the parking lamp or On
position the Instrument Cluster sends a J1850 mes-
sage to the Front Control Module, which is mated to
the power distribution center to become the Inte-
grated Control Module, to illuminate the appropriate
bulbs. When the multifunction switch is activated to
the optical horn or high beam position the Instru-
ment Cluster illuminates the high beam indicator
and sends a J1850 message to the Front Control
Module to illuminate the appropriate bulbs.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the left instrument panel bezel. (Refer
to 23 - BODY/INSTRUMENT PANEL/CLUSTER
BEZEL - REMOVAL).
(3) Disconnect the harness connector.(4) Remove the screws that secure the headlamp
switch to the instrument panel bezel (Fig. 9).
(5) Remove the headlamp switch from the instru-
ment panel bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Position the headlamp switch to the left instru-
ment panel bezal and secure with screws.Tighten the
screws to 2.2 N´m (20 in. lbs.).
(2) Reconnect the instrument panel wire harness
connector for the headlamp switch.
(3) Position the left instrument panel bezal on to
the instrument panel.
Fig. 9 Headlamp Switch Removal
1 - DASH BOARD
2 - HEADLAMP SWITCH
3 - INSTRUMENT PANEL BEZAL
8L - 14 LAMPS/LIGHTING - EXTERIORDR

lobe, pushing on the cancel actuator, returns the
switch to the OFF position.
OPERATION - TURN SIGNAL SYSTEM
The Instrument Cluster monitors the multiplexed
multifunction switch. In a turning event the Instru-
ment Cluster senses a change in the turn signal
lever and illuminates the appropriate turn signal
indicator. At the same time, the Instrument Cluster
will send a J1850 message on the PCI bus to the
Front Control Module (FCM). The FCM will respond
by activating the appropriate relay in the Power Dis-
tribution Center.
A chime will sound after the turn is completed if
vehicle has traveled a distance of approximately 1.0
mile and a speed of 15 mph, with the turn signal ON.
DIAGNOSIS AND TESTING - MULTI-FUNCTION
SWITCH
To test the turn signal, headlamp beam select and
optical horn portion of the multi-function switch:
(1) Remove the multi-function switch, refer to
Electrical, Lamps/Lighting - Exterior, Multi-Function
Switch, Removal, and Installation.
(2) Using an ohmmeter check the resistance read-
ings between multi-function switch pins. Refer to
Wiring Diagrams for proper pin numbers and the
MULTI-FUNCTION SWITCH TESTS table.
MULTI-FUNCTION SWITCH TESTS
EXTERIOR LIGHTING FUNCTIONS
SWITCH POSITION CONNECTOR PINS RESISTANCE (OHMS)
Off 1 - 2 Open
Headlamp High Beams On 1 - 2 518 - 575
Hazard 3 - 2 115 - 128
Optical Horn (Flash-to-Pass) On 1 - 2 1257 - 1397
Off 3 - 2 2643 - 2937
Turn Signal Left 3 - 2 345 - 384
Turn Signal Right 3 - 2 786 - 873
FRONT WIPER FUNCTIONS
SWITCH POSITION CONNECTOR PINS RESISTANCE (OHMS)  10%
Front Wiper Off 2 - 4 6910 - 7678
Delay 1 2 - 4 2128 - 2365
Delay 2 2 - 4 1089 - 1210
Delay 3 2 - 4 627 - 697
Delay 4 2 - 4 388 - 431
Delay 5 2 - 4 234 - 261
Front Wiper Low 2 - 4 125 - 140
Front Wiper High 2 - 4 50 - 56
Wash 1 - 2 2584 - 2871
REMOVAL
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO THE ELECTRICAL RESTRAINT
SYSTEM FOR SERVICE PROCEDURES. FAILURE
TO DO SO MAY RESULT IN ACCIDENTAL DEPLOY-
MENT OF THE AIRBAG AND POSSIBLE PERSONAL
INJURY(1) Disconnect and isolate battery negative cable.
(2) Remove the steering wheel and the upper and
lower steering column shrouds. Refer to Steering,
Column, Shroud, Removal.
(3) Disconnect the wire connector from the back of
the multi-function switch.
(4) Remove the screws retaining the multi-function
switch to the steering column adapter collar (Fig. 15).
(5) Remove the multi-function switch.
8L - 18 LAMPS/LIGHTING - EXTERIORDR
MULTI-FUNCTION SWITCH (Continued)

(6) Remove the screws retaining the clock spring
to the multifunction switch.
INSTALLATION
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO THE ELECTRICAL RESTRAINT
SYSTEM FOR SERVICE PROCEDURES. FAILURE
TO DO SO MAY RESULT IN ACCIDENTAL DEPLOY-
MENT OF THE AIRBAG AND POSSIBLE PERSONAL
INJURY.
(1) Install the clock spring on the multifunction
switch.
(2) Position the switch on to the steering column.
(3) Install the retaining screws (Fig. 15).
(4) Connect the wire harness connector.
(5) Install the upper, lower steering column
shrouds and the steering wheel. Refer to Steering,
Column, Shroud, Installation.
(6) Connect the battery negative cable.
PARK LAMP RELAY
DESCRIPTION
The park lamp relay is located in the Power Dis-
tribution Center (PDC) of the vehicle. The park lamprelay is a conventional International Standards
Organization (ISO) micro relay (Fig. 16). Relays con-
forming to the ISO specifications have common phys-
ical dimensions, current capacities, terminal
patterns, and terminal functions.
The park lamp relay cannot be adjusted or
repaired and, if faulty or damaged, the unit must be
replaced.
OPERATION
The park lamp relay is an electromechanical
switch that uses a low current input from the Front
Control Module (FCM) to control a high current out-
put to the park lamps. The movable common feed
contact point is held against the fixed normally
closed contact point by spring pressure. When the
relay coil is energized, an electromagnetic field is
produced by the coil windings. This electromagnetic
field draws the movable relay contact point away
from the fixed normally closed contact point, and
holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. A
resistor is connected in parallel with the relay coil in
the relay, and helps to dissipate voltage spikes and
electromagnetic interference that can be generated as
the electromagnetic field of the relay coil collapses.
The park lamp relay terminals are connected to
the vehicle electrical system through a connector in
the Junction Block (JB). The inputs and outputs of
the headlamp low beam relay include:
²Common Feed Terminal- The common feed
terminal (30) is connected to the park lamps through
Fig. 15 MULTIFUNCTION SWITCH
1 - SCREW
2 - COLUMN
3 - CLOCK SPRING
4 - MULTI - FUNCTION SWITCH
Fig. 16 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DRLAMPS/LIGHTING - EXTERIOR 8L - 19
MULTI-FUNCTION SWITCH (Continued)

the park lamp relay output circuit and provides
ground to the park lamps when the relay is de-ener-
gized, and battery current to the park lamps when-
ever the relay is energized.
²Coil Ground Terminal- The coil ground termi-
nal (85) is connected to a control output of the Front
Control Module (FCM) through a park lamp relay
control circuit. The FCM controls park lamp opera-
tion by controlling a ground path through this cir-
cuit.
²Coil Battery Terminal- The coil battery ter-
minal (86) receives battery current at all times from
a fuse in the PDC through a fused B(+) circuit.
²Normally Open Terminal- The normally open
terminal (87) receives battery current at all times
from a fuse in the Power Distribution Center (PDC)
through a fused B(+) circuit.
²Normally Closed Terminal- The normally
closed terminal (87A) is connected to ground at all
times.
The park lamp relay can be diagnosed using con-
ventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - PARK LAMP
RELAY
The park lamp relay (Fig. 17) is located in the
Power Distribution Center (PDC). Refer to the appro-
priate wiring information.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Remove the park lamp relay from the PDC.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the Power Distribution Center (PDC)
cover.
(3) Remove the park lamp relay by grasping it
firmly and pulling it straight out from the receptacle
in the PDC.
Fig. 17 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8L - 20 LAMPS/LIGHTING - EXTERIORDR
PARK LAMP RELAY (Continued)

INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Position the park lamp relay to the proper
receptacle in the Power Distribution Center (PDC).
(2) Align the park lamp relay terminals with the
terminal cavities in the PDC.
(3) Press firmly and evenly on the top of the park
lamp relay until the terminals are fully seated in the
PDC.
(4) Install the PDC cover.
(5) Reconnect the battery negative cable.
PARK/TURN SIGNAL LAMP
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the headlamp unit.(Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - REMOVAL).
(3) Seperate the socket from the headlamp unit.
(4) Release the bulb socket locking tabs and seper-
ate the bulb from the socket (Fig. 18).
INSTALLATION
(1) Install the bulb into the socket.
(2) Install the socket into the headlamp unit.
(3) Install the headlamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - INSTALLATION).
(4) Connect the negative battery cable.
TAIL LAMP
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - REMOVAL).
(3) Remove the bulb back plate from the tail lamp
unit.
(4) Release the bulb locking tabs and remove the
bulb from the back plate (Fig. 18).
INSTALLATION
(1) Install the bulb into the back plate.
(2) Install the bulb back plate to the tail lamp
unit.
(3) Install the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - INSTALLATION).
(4) Connect the negative battery cable.
TAIL LAMP UNIT
REMOVAL
(1) Lower the tail gate.
(2) Remove the screws
(3) Disengage the taillamp unit from the body
panel.
(4) Disconnect the electrical connector (Fig. 19).
INSTALLATION
(1) Connect the wiring harness connector.
(2) Position the taillamp unit into the body panel.
(3) Install the screws (Fig. 19).
Fig. 18 Pull Bulb From Socket
1 - SOCKET
2 - BULB
DRLAMPS/LIGHTING - EXTERIOR 8L - 21
PARK LAMP RELAY (Continued)

On models equipped with optional side curtain air-
bags, the ACM communicates with both the left and
right Side Impact Airbag Control Modules (SIACM)
over the PCI data bus. The SIACM notifies the ACM
when it has detected a monitored system fault and
stored a DTC in memory for its respective side cur-
tain airbag system, and the ACM sets a DTC and
controls the airbag indicator operation accordingly.
The ACM receives battery current through two cir-
cuits; a fused ignition switch output (run) circuit
through a fuse in the Integrated Power Module
(IPM), and a fused ignition switch output (run-start)
circuit through a second fuse in the IPM. The ACM
receives ground through a ground circuit and take
out of the instrument panel wire harness. This take
out has a single eyelet terminal connector that is
secured by a ground screw to the instrument panel
support structure. These connections allow the ACM
to be operational whenever the ignition switch is in
the Start or On positions. The ACM also contains an
energy-storage capacitor. When the ignition switch is
in the Start or On positions, this capacitor is contin-
ually being charged with enough electrical energy to
deploy the front supplemental restraint components
for up to one second following a battery disconnect or
failure. The purpose of the capacitor is to provide
backup supplemental restraint system protection in
case there is a loss of battery current supply to the
ACM during an impact.
Two sensors are contained within the ACM; an
electronic impact sensor, and a safing sensor. The
electronic impact sensor is an accelerometer that
senses the rate of vehicle deceleration, which pro-
vides verification of the direction and severity of an
impact. The safing sensor is an electromechanical
sensor within the ACM that provides an additional
logic input to the ACM microprocessor. The safing
sensor is a normally open switch that is used to ver-
ify the need for a front supplemental restraint
deployment by detecting impact energy of a lesser
magnitude than that of the electronic impact sensor,
and must be closed in order for the front airbags or
seat belt tensioners to deploy. A pre-programmed
decision algorithm in the ACM microprocessor deter-
mines when the deceleration rate as signaled by the
impact sensor and the safing sensor indicate an
impact that is severe enough to require front supple-
mental restraint system protection and, based upon
the status of the passenger airbag on/off switch input
and the severity of the monitored impact, determines
what combination of seat belt tensioner and front air-
bag deployment is required for each front seating
position. When the programmed conditions are met,
the ACM sends the proper electrical signals to deploy
the seat belt tensioners and dual front airbags.The hard wired inputs and outputs for the ACM
may be diagnosed and tested using conventional
diagnostic tools and procedures. However, conven-
tional diagnostic methods will not prove conclusive in
the diagnosis of the ACM, the PCI data bus network,
or the electronic message inputs to and outputs from
the ACM. The most reliable, efficient, and accurate
means to diagnose the ACM, the PCI data bus net-
work, and the electronic message inputs to and out-
puts from the ACM requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS OR SERVICE.
THIS IS THE ONLY SURE WAY TO DISABLE THE
SUPPLEMENTAL RESTRAINT SYSTEM. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
WARNING: THE AIRBAG CONTROL MODULE CON-
TAINS THE IMPACT SENSOR, WHICH ENABLES
THE SYSTEM TO DEPLOY THE FRONT SUPPLE-
MENTAL RESTRAINTS. NEVER STRIKE OR DROP
THE AIRBAG CONTROL MODULE, AS IT CAN DAM-
AGE THE IMPACT SENSOR OR AFFECT ITS CALI-
BRATION. IF AN AIRBAG CONTROL MODULE IS
ACCIDENTALLY DROPPED DURING SERVICE, THE
MODULE MUST BE SCRAPPED AND REPLACED
WITH A NEW UNIT. FAILURE TO OBSERVE THIS
WARNING COULD RESULT IN ACCIDENTAL,
INCOMPLETE, OR IMPROPER FRONT SUPPLEMEN-
TAL RESTRAINT DEPLOYMENT AND POSSIBLE
OCCUPANT INJURIES.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) On models with a manual transmission,
remove the floor console from the top of the floor
panel transmission tunnel. (Refer to 23 - BODY/IN-
TERIOR/FLOOR CONSOLE - REMOVAL).
(3) On models with an automatic transmission,
remove the ACM cover from the instrument panel.
DRRESTRAINTS 8O - 11
AIRBAG CONTROL MODULE (Continued)

SPEED CONTROL
TABLE OF CONTENTS
page page
SPEED CONTROL
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - VACUUM
SUPPLY TEST.........................2
DIAGNOSIS AND TESTING - ROAD TEST....3
SPECIFICATIONS
TORQUE - SPEED CONTROL.............3
CABLE
DESCRIPTION..........................3
OPERATION............................3
REMOVAL.............................3
INSTALLATION..........................6
SERVO
DESCRIPTION..........................6OPERATION............................7
REMOVAL.............................7
INSTALLATION..........................7
SWITCH
DESCRIPTION..........................8
OPERATION............................8
REMOVAL.............................9
INSTALLATION..........................9
VACUUM RESERVOIR
DESCRIPTION..........................9
OPERATION............................9
DIAGNOSIS AND TESTING - VACUUM
RESERVOIR..........................9
REMOVAL.............................10
INSTALLATION.........................10
SPEED CONTROL
DESCRIPTION
All 3.7L/4.7L/5.9L/8.0LGas Engines and/or Diesel
With Automatic Trans.
The speed control system is operated by the use of
a cable and a vacuum controlled servo. Electronic
control of the speed control system is integrated into
the Powertrain Control Module (PCM). The controls
consist of two steering wheel mounted switches. The
switches are labeled: ON/OFF, RES/ACCEL, SET,
COAST, and CANCEL.
The system is designed to operate at speeds above
30 mph (50 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO
NOT PERMIT MAINTAINING A CONSTANT SPEED,
SUCH AS IN HEAVY TRAFFIC OR ON ROADS THAT
ARE WINDING, ICY, SNOW COVERED, OR SLIP-
PERY.
5.7L Gas
The speed control system is fully electronically con-
trolled by the Powertrain Control Module (PCM).A
cable and a vacuum controlled servo are not
used. This is a servo-less system.The controls
consist of two steering wheel mounted switches. Theswitches are labeled: ON/OFF, RES/ACCEL, SET,
COAST, and CANCEL.
The system is designed to operate at speeds above
30 mph (50 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO
NOT PERMIT MAINTAINING A CONSTANT SPEED,
SUCH AS IN HEAVY TRAFFIC OR ON ROADS THAT
ARE WINDING, ICY, SNOW COVERED, OR SLIP-
PERY.
5.9L Diesel With Manual Trans.
The speed control system is fully electronically con-
trolled by the Engine Control Module (ECM).A
cable and a vacuum controlled servo are not
used if the vehicle is equipped with a manual
transmission and a diesel engine. This is a ser-
vo-less system.The controls consist of two steering
wheel mounted switches. The switches are labeled:
ON/OFF, RES/ACCEL, SET, COAST, and CANCEL.
The system is designed to operate at speeds above
30 mph (50 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO
NOT PERMIT MAINTAINING A CONSTANT SPEED,
SUCH AS IN HEAVY TRAFFIC OR ON ROADS THAT
ARE WINDING, ICY, SNOW COVERED, OR SLIP-
PERY.
DRSPEED CONTROL 8P - 1

REMOVAL
Depending on engine control computer (JTEC
having a 3±plug connector or 5.7L V-8 NGC hav-
ing a 4±plug connector), 2 types of switches are
used. Both types of switches are internally and
externally different. The switches used with the
NGC system have attached pigtail leads (Fig.
11). The switch used with the JTEC system does
not have an attached pigtail lead.
(1) Remove switch mounting screw (Fig. 10). or
(Fig. 11)
(2) Pull switch from steering wheel.
(3) Unplug electrical connector from switch (Fig.
10), or, switch pigtail wire harness from steering
wheel wire harness (Fig. 11) and remove switch.
INSTALLATION
(1) Plug electrical connector into switch (Fig. 10),
or connect pigtail wire harness to steering wheel wire
harness (Fig. 11). Be sure wires are not pinched.
(2) Position switch to steering wheel.
(3) Install switch mounting screw and tighten.
Refer to torque specifications.
VACUUM RESERVOIR
DESCRIPTION
The vacuum reservoir is a plastic storage tank con-
nected to an engine vacuum source by vacuum lines.
A vacuum reservoir is not used with diesel engines or
the 5.7L gas powered engine.
OPERATION
The vacuum reservoir is used to supply the vac-
uum needed to maintain proper speed control opera-
tion when engine vacuum drops, such as in climbing
a grade while driving. A one-way check valve is used
in the vacuum line between the reservoir and the
vacuum source. This check valve is used to trap
engine vacuum in the reservoir. On certain vehicle
applications, this reservoir is shared with the heat-
ing/air-conditioning system. The vacuum reservoir
cannot be repaired and must be replaced if faulty.
DIAGNOSIS AND TESTING - VACUUM
RESERVOIR
(1) Disconnect vacuum hose at speed control servo
and install a vacuum gauge into the disconnected
hose.
Fig. 10 SPEED CONTROL SWITCHES (EXCEPT 5.7L
V-8 ENGINE)
1 - ELECTRICAL CONNECTORS
2 - MOUNTING SCREWS
3 - RIGHT SWITCH
4 - LEFT SWITCH
Fig. 11 SPEED CONTROL SWITCHES (WITH 5.7L V-8
ENGINE)
1 - MOUNTING SCREWS
2 - RIGHT SWITCH
3 - LEFT SWITCH
4 - PIGTAIL LEADS
DRSPEED CONTROL 8P - 9
SWITCH (Continued)

VEHICLE THEFT SECURITY
TABLE OF CONTENTS
page page
VEHICLE THEFT SECURITY
DESCRIPTION
DESCRIPTION........................1
SENTRY KEY IMMOBILIZER SYSTEM (SKIS) . 1
DESCRIPTION........................1
OPERATION
OPERATION..........................2
OPERATION..........................2
OPERATION..........................2
DIAGNOSIS AND TESTING
VEHICLE THEFT SECURITY SYSTEM......3STANDARD PROCEDURE
CONFIGURING A NEW MODULE / SWITCH
OPERATING MODES....................3
SENTRY KEY IMMOBILIZER SYSTEM
INITIALIZATION........................3
SENTRY KEY IMMOBILIZER SYSTEM
TRANSPONDER PROGRAMMING..........4
SENTRY KEY IMMOBILIZER SYSTEM
INDICATOR LAMP
DESCRIPTION..........................5
OPERATION............................5
VEHICLE THEFT SECURITY
DESCRIPTION
DESCRIPTION
The Vehicle Theft/Security System (VTSS) is
designed to protect against whole vehicle theft. The
system monitors the vehicle doors and ignition for
unauthorized operation.
The VTSS activates:
²Sounding of the horn
²Flashing of the park lamps
²Flashing of the head lamps
The Remote Keyless Entry (RKE) has 1 mode of
operation,CUSTOMER USAGEmode. The cus-
tomer usage mode provides full functionality of the
module and is the mode in which the RKE module
should be operating when used by the customer.
SENTRY KEY IMMOBILIZER SYSTEM (SKIS)
The Sentry Key Immobilizer System (SKIS) is
designed to provide passive protection against unau-
thorized vehicle use by preventing the engine from
operating while the system is armed. The primary
components of this system are the Sentry Key Immo-
bilizer Module (SKIM), the Sentry Key transponder,
the Vehicle Theft/Security System (VTSS) indicator
LED, and the Powertrain Control Module (PCM).
The SKIM is installed on the steering column near
the ignition lock cylinder. The transponder is located
under the molded rubber cap on the head of the igni-tion key. The VTSS indicator LED is located in the
instrument cluster.
The SKIS includes two valid Sentry Key transpon-
ders from the factory. This is so the customer can self
program new keys if one is lost. If the customer
wishes, additional non-coded blank Sentry Keys are
available. These blank keys can be cut to match a
valid ignition key, but the engine will not start
unless the key transponder is also programmed to
the vehicle. The SKIS will recognize no more than
eight valid Sentry Key transponders at any one time.
The SKIS performs a self-test each time the igni-
tion switch is turned to the ON position, and will
store Diagnostic Trouble Codes (DTC's) if a system
malfunction is detected. The SKIS can be diagnosed,
and any stored DTC can be retrieved using a
DRBIIItscan tool as described in the proper Body
Diagnostic Procedures Manual.
DESCRIPTION
The Sentry Key Immobilizer Module (SKIM) con-
tains a Radio Frequency (RF) transceiver and a cen-
tral processing unit, which includes the Sentry Key
Immobilizer System (SKIS) program logic. The SKIS
programming enables the SKIM to program and
retain in memory the codes of at least two, but no
more than eight electronically coded Sentry Key
transponders. The SKIS programming also enables
the SKIM to communicate over the Programmable
Communication Interface (PCI) bus network with the
Powertrain Control Module (PCM), and/or the
DRBIIItscan tool.
DRVEHICLE THEFT SECURITY 8Q - 1

OPERATION
OPERATION
When in theCustomer Usagemode of operation,
the system is armed when the vehicle is locked using
the:
²Power Door Lock Switches
²Remote Keyless Entry (RKE) Transmitter
²Key Cylinder Switches
After the vehicle is locked and the last door is
closed, the VTSS indicator in the instrument cluster
will flash quickly for 16 seconds, indicating that the
arming is in process. After 16 seconds, the LED will
continue to flash at a slower rate indicating that the
system is armed.
VTSS disarming occurs upon normal vehicle entry
by unlocking either door via the key cylinder or RKE
transmitter, or by starting the vehicle with a valid
Sentry Key. This disarming will also halt the alarm
once it has been activated.
A tamper alert exists to notify the driver that the
system has been activated. This alert consists of 3
horn pulses and the security telltail flashing for 30
seconds when the vehicle is disarmed. The tamper
alert will not occur if disarmed while alarming.
The VTSS will not arm by mechanically locking the
vehicle doors. This will manually override the sys-
tem.
OPERATION
The SKIS includes two valid Sentry Key transpon-
ders from the factory. These two Sentry Keys can be
used to program additional non-coded blank Sentry
Keys. These blank keys can be cut to match a valid
ignition key, but the engine will not start unless the
key transponder is also programmed to the vehicle.
The SKIS will recognize no more than eight valid
Sentry Key transponders at any one time.
The SKIS performs a self-test each time the igni-
tion switch is turned to the ON position, and will
store Diagnostic Trouble Codes (DTC's) if a system
malfunction is detected. The SKIS can be diagnosed,
and any stored DTC can be retrieved using a
DRBIIItscan tool as described in the proper Power-
train Diagnostic Procedures manual.
OPERATION
The SKIM transmits and receives RF signals
through a tuned antenna enclosed within a molded
plastic ring formation that is integral to the SKIM
housing. When the SKIM is properly installed on the
steering column, the antenna ring is oriented around
the circumference of the ignition lock cylinder hous-
ing. This antenna ring must be located within eight
millimeters (0.31 inches) of the Sentry Key in orderto ensure proper RF communication between the
SKIM and the Sentry Key transponder.
For added system security, each SKIM is pro-
grammed with a unique ªSecret Keyº code and a
security code. The SKIM keeps the ªSecret Keyº code
in memory. The SKIM also sends the ªSecret Keyº
code to each of the programmed Sentry Key tran-
sponders. The security code is used by the assembly
plant to access the SKIS for initialization, or by the
dealer technician to access the system for service.
The SKIM also stores in its memory the Vehicle
Identification Number (VIN), which it learns through
a PCI bus message from the PCM during initializa-
tion.
The SKIM and the PCM both use software that
includes a rolling code algorithm strategy, which
helps to reduce the possibility of unauthorized SKIS
disarming. The rolling code algorithm ensures secu-
rity by preventing an override of the SKIS through
the unauthorized substitution of the SKIM or the
PCM. However, the use of this strategy also means
that replacement of either the SKIM or the PCM
units will require a system initialization procedure to
restore system operation.
When the ignition switch is turned to the ON or
START positions, the SKIM transmits an RF signal
to excite the Sentry Key transponder. The SKIM then
listens for a return RF signal from the transponder
of the Sentry Key that is inserted in the ignition lock
cylinder. If the SKIM receives an RF signal with
valid ªSecret Keyº and transponder identification
codes, the SKIM sends a ªvalid keyº message to the
PCM over the PCI bus. If the SKIM receives an
invalid RF signal or no response, it sends ªinvalid
keyº messages to the PCM. The PCM will enable or
disable engine operation based upon the status of the
SKIM messages.
The SKIM also sends messages to the Instrument
Cluster which controls the VTSS indicator. The
SKIM sends messages to the Instrument Cluster to
turn the indicator on for about three seconds when
the ignition switch is turned to the ON position as a
ªbulbº test. After completion of the ªbulbº test, the
SKIM sends bus messages to keep the indicator off
for a duration of about one second. Then the SKIM
sends messages to turn the indicator on or off based
upon the results of the SKIS self-tests. If the VTSS
indicator comes on and stays on after the ªbulb testº,
it indicates that the SKIM has detected a system
malfunction and/or that the SKIS has become inoper-
ative.
If the SKIM detects an invalid key when the igni-
tion switch is turned to the ON position, it sends
messages to flash the VTSS indicator. The SKIM can
also send messages to flash the indicator to serve as
an indication to the customer that the SKIS has been
8Q - 2 VEHICLE THEFT SECURITYDR
VEHICLE THEFT SECURITY (Continued)