SPEED CONTROL
TABLE OF CONTENTS
page page
SPEED CONTROL
DESCRIPTION..........................1
OPERATION
OPERATION..........................1
OPERATION - INTERACTIVE SPEED
CONTROL (4 Speed EATX Only)...........2
DIAGNOSIS AND TESTING - ROAD TEST.....3
SPECIFICATIONS - TORQUE...............3
CABLE
DESCRIPTION..........................4
OPERATION............................4
REMOVAL.............................4
INSTALLATION..........................4
SERVO
DESCRIPTION..........................4OPERATION............................4
REMOVAL.............................4
INSTALLATION..........................4
SWITCH
DESCRIPTION..........................5
OPERATION............................5
REMOVAL.............................5
INSTALLATION..........................6
VACUUM RESERVOIR
DESCRIPTION..........................6
OPERATION............................6
REMOVAL.............................6
INSTALLATION..........................6
SPEED CONTROL
DESCRIPTION
The speed control system is electronically con-
trolled and vacuum operated. The electronic control
is integrated into the Powertrain Control Module.
The controls are located on the steering wheel. The
ON/OFF, and SET buttons are located on the left side
of the airbag module. The RESUME/ACCEL, CAN-
CEL and COAST buttons are located on the right
side of the airbag module (Fig. 1).The system is designed to operate at speeds above
30 mph (48 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.
OPERATION
OPERATION
When speed control is activated by depressing the
ON switch, the PCM allows a set speed to be stored
in RAM for speed control. To store a set speed,
depress and release the SET switch while the vehicle
is moving at a speed between 25 and 85 mph. In
order for the speed control to engage, the brakes can-
not be applied, nor can the gear selector be indicat-
ing the transmission is in Park or Neutral (ATX) or
1st/2nd gear (MTX). The speed control can be disen-
gaged manually by:
²Stepping on the brake pedal
²Depressing the OFF switch
²Depressing the CANCEL switch.
²Depressing the clutch pedal
²Operating in 1st or 2nd gear (autostick, if
equipped)
Fig. 1 SPEED CONTROL SWITCHES - Typical
RSSPEED CONTROL8P-1
OPERATION
The PCM on NGC vehicles first senses that the
speed control is set. If the set speed is exceeded by
more than 4 mph (6.5 km/hr) and the throttle is
closed, the PCM on NGC vehicles causes the trans-
axle to downshift to THIRD gear. After downshifting,
the automatic speed control resumes normal opera-
tion. To ensure that an upshift is appropriate after
the set speed is reached, the PCM on NGC vehicles
waits until the speed control system opens the throt-
tle at least 6 degrees before upshifting to OVER-
DRIVE again.
If the driver applies the brakes, canceling auto-
matic speed control operation with the transaxle still
in THIRD gear, the PCM on NGC vehicles maintains
this gear until the driver opens the throttle at least 6
degrees to avoid an inappropriate upshift. The
upshift is also delayed for 2.5 seconds after reaching
the 6 degrees throttle opening in anticipation that
the driver might open the throttle enough to require
THIRD gear. This will avoid unnecessary and dis-
turbing transmission cycling. If the automatic speed
control RESUME feature is used after braking, the
upshift is delayed until the set speed is achieved to
reduce cycling and provide better response.
DIAGNOSIS AND TESTING - ROAD TEST
Perform a vehicle road test to verify reports of
speed control system malfunction. The road test
should include attention to the speedometer. Speed-
ometer operation should be smooth and without flut-
ter at all speeds.Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer problems should
be corrected before proceeding. Refer to the Instru-
ment Cluster for speedometer diagnosis.
If a road test verifies an inoperative system, and
the speedometer operates properly, check for:
²A Diagnostic Trouble Code (DTC). If a DTC
exists, conduct tests per the Powertrain Diagnostic
Procedures manual.
²A misadjusted brake (stop) lamp switch. This
could also cause an intermittent problem.
²Loose or corroded electrical connections at the
servo. Corrosion should be removed from electrical
terminals and a light coating of Mopar Multipurpose
Grease, or equivalent, applied.
²Leaking vacuum reservoir.
²Loose or leaking vacuum hoses or connections.
²Defective one-way vacuum check valve.
²Secure attachment at both ends of the speed
control servo cable.
²Smooth operation of throttle linkage and throttle
body air valve.
²Conduct electrical test at PCM.
²Failed speed control servo. Do the servo vacuum
test.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals or seals. If
these components are damaged, intermittent or
complete system failure may occur.
SPECIFICATIONS - TORQUE
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Servo Mounting Bracket
Nuts14 10.3 123.9
Servo Mounting Bracket
Bolts14 10.3 123.9
Servo Mounting Nuts 6.7 60
RSSPEED CONTROL8P-3
SPEED CONTROL (Continued)
CABLE
DESCRIPTION
The speed control servo cable is connected between
the speed control vacuum servo diaphragm and the
throttle body control linkage.
OPERATION
This cable causes the throttle control linkage to
open or close the throttle valve in response to move-
ment of the vacuum servo diaphragm.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove speed control cable from throttle cam
by sliding clasp out hole used for throttle cable.
(3) Compress the retaining tabs on the cable and
slide cable out of bracket.
(4) Disconnect electrical connectors and vacuum
hose from servo.
(5) Remove two nuts attaching speed control cable
and mounting bracket to servo.
(6) Pull cable away from servo to expose retaining
clip and remove clip attaching cable to servo.
(7) Remove speed control cable.
INSTALLATION
(1) Slide cable into throttle cable bracket and
engage retaining tabs.
(2) Rotate the throttle cam forward to the wide
open position and install speed control cable clasp.
(3) Rotate the throttle cam forward to the wide
open position and install throttle cable clasp.
(4) Install retaining clip that attaches cable to
servo.
(5) Insert servo studs through holes in the mount-
ing bracket and speed control cable.
(6) Install nuts, tighten to 6.7 N´m (60 in. lbs.).
(7) Connect vacuum hose to servo.
(8) Connect electrical connector.
(9) Install servo and bracket and tighten nuts and
bolt.
(10) Connect negative battery cable.
SERVO
DESCRIPTION
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The solenoid valve body con-
tains three solenoids:
²Vacuum
²Vent
²Dump
The vacuum chamber contains a diaphragm with a
cable attached to control the throttle linkage.
OPERATION
The PCM controls the solenoid valve body. The
solenoid valve body controls the application and
release of vacuum to the diaphragm of the vacuum
servo. The servo unit cannot be repaired and is ser-
viced only as a complete assembly.
Power is supplied to the servo by the PCM through
the brake switch. The PCM controls the ground path
for the vacuum and vent solenoids.
The dump solenoid is energized anytime it receives
power. If power to the dump solenoid is interrupted,
the solenoid dumps vacuum in the servo. This pro-
vides a safety backup to the vent and vacuum sole-
noids.
The vacuum and vent solenoids must be grounded
by the PCM to operate. When the PCM grounds the
vacuum servo solenoid, the solenoid allows vacuum
to enter the servo and pull open the throttle plate
using the cable. When the PCM breaks the ground,
the solenoid closes and no more vacuum is allowed to
enter the servo. The PCM also operates the vent sole-
noid via ground. The vent solenoid opens and closes a
passage to bleed or hold vacuum in the servo as
required.
The PCM cycles the vacuum and vent solenoids to
maintain the set speed, or to accelerate and deceler-
ate the vehicle. To increase throttle opening, the
PCM grounds the vacuum and vent solenoids. To
decrease throttle opening, the PCM removes the
grounds from the vacuum and vent solenoids.
REMOVAL
(1) Release hood latch and open hood.
(2) Disconnect the negative battery cable.
(3) Disconnect the throttle and speed control cable
ends from throttle body (Fig. 2).
(4) Depress lock tabs holding speed control and
throttle cable casing to cable mount bracket.
(5) Disconnect vacuum line from speed control
servo that leads to the battery tray/vacuum reservoir.
(6) Remove battery tray/vacuum reservoir, refer to
the Battery section for more information (Fig. 3).
(7) Remove speed control servo and bracket (Fig.
4).
(8) Disconnect wire connector from speed control
servo.
(9) Remove speed control servo.
INSTALLATION
Transfer speed control cable to replacement speed
control servo.
(1) Install retaining clip to cable at servo.
(2) Install 2 nuts at cable to servo and servo
bracket, tighten to 7 N´m (60 ins. lbs.).
(3) Connect electrical connector to servo.
8P - 4 SPEED CONTROLRS
(4) Connect vacuum line to speed control servo
that leads to the battery tray/vacuum reservoir.
(5) Install speed control servo and bracket.
(6) Install battery tray/vacuum reservoir, refer to
the Battery section for more information.
(7) Install speed control and throttle cable casing
to cable mount bracket.
(8) Connect the throttle and speed control cable
ends to throttle body.
(9) Connect the negative battery cable.
SWITCH
DESCRIPTION
There are two separate switch pods that operate
the speed control system and are located on the
steering wheel.
OPERATION
The speed control system has five separate resis-
tive switches that provide a single multiplexed
(MUX) voltage inputs to the PCM.The switch names
are: ON, OFF, SET, COAST, RESUME, ACCEL, TAP-
UP, COAST, and CANCEL. Based on conditions when
the buttons are pushed (and released), the five volt-
age ranges provided to the PCM result in the follow-
ing functions: ON, OFF, SET, COAST, RESUME,
ACCEL, TAP-UP, TAP-DOWN, COAST, and CAN-
CEL. Refer to the Speed Control Section for more
information
Also the PCM receives an input from the brake
switch to sense whether the brake pedal has been
depressed. When the PCM receives the brake
depressed input, it turns off power to the speed con-
trol servo and disengages speed control. Also the
power to the servo is supplied through the brake
switch, which opens the circuit when the brake pedal
is depressed.
The individual switches cannot be repaired. If one
switch fails, the entire switch module must be
replaced.
REMOVAL
The speed control switches are mounted in the
steering wheel and wired through the clock spring
device under the airbag module.
Fig. 2 Speed Control Cable End
1 - SPEED CONTROL VACUUM HOSE
2 - THROTTLE BODY
3 - SPEED CONTROL CABLE
Fig. 3 BATTERY TRAY/VACUUM RESERVOIR
Fig. 4 SPEED CONTROL SERVO
RSSPEED CONTROL8P-5
SERVO (Continued)
WARNING: IF REMOVAL OF AIRBAG MODULE IS
NECESSARY, REFER TO THE RESTRAINT SYS-
TEMS SECTION FOR MORE INFORMATION.
(1) Remove the negative battery cable.
(2) Turn off ignition.
(3) Remove the air bag, refer to the restraint sec-
tion for more information.
(4) Remove the screw from bottom of the switch.
(5) Remove switch from steering wheel.
(6) Disconnect two-way electrical connector.
(7) Repeat for the other switch.
INSTALLATION
The speed control switches are mounted in the
steering wheel and wired through the clock spring
device under the airbag module.
WARNING: IF REMOVAL OF AIRBAG MODULE IS
NECESSARY, REFER TO THE RESTRAINT SYS-
TEMS SECTION FOR MORE INFORMATION.
(1) Connect two-way electrical connector.
(2) Install switch.
(3) Install screw for the switch.
(4) Repeat for the other switch.
(5) Install the air bag, refer to the restraint section
for more information.
(6) Install the negative battery cable.
VACUUM RESERVOIR
DESCRIPTION
The vacuum reservoir is located in the engine com-
partment. It is made of plastic.
OPERATION
The reservoir stores engine vacuum. Manifold vac-
uum is supplied from the brake booster check valve.
The speed control vacuum supply hose has a check
valve at the source (brake booster) to maintain the
highest available vacuum level in the servo, reservoir
and vacuum hoses. When engine vacuum drops, as in
climbing a grade while driving, the reservoir supplies
the vacuum needed to maintain proper speed control
operation. The vacuum reservoir cannot be repaired
and must be replaced if faulty.
REMOVAL
(1) Release hood latch and open hood.
(2) Disconnect the negative battery cable.
(3) Disconnect the vacuum line to the battery tray/
vacuum reservoir.
(4) Remove battery tray/vacuum reservoir, refer to
the Battery section for more information.
INSTALLATION
(1) Install battery tray/vacuum reservoir, refer to
the Battery section for more information.
(2) Connect vacuum line that leads to the battery
tray/vacuum reservoir.
(3) Connect the negative battery cable.
8P - 6 SPEED CONTROLRS
SWITCH (Continued)
²WIPE AFTER WASH- Wipers operate at low
speed in any mode setting. Wipers operate only while
the wash button is depressed with switch in the OFF
mode and wipers stop in mid-cycle when button is
released.The windshield wiper park switch and circuit is
monitored by the BCM. The park switch and circuit
can be tested using the WIPER SYSTEM DIAGNO-
SIS table.
WIPER SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
WIPER BLADES DO NOT
PARK PROPERLY1. WIPER ARMS IMPROPERLY
PARKED.1. REMOVE WIPER ARMS AND REPARK.
REFER TO WIPER ARM REMOVAL AND
INSTALLATION.
2. WIPER ARMS ARE LOOSE ON
PIVOT SHAFT.2. REMOVE WIPER ARM AND REPARK.
REFER TO WIPER ARM REMOVAL AND
INSTALLATION.
3. MOTOR CRANK LOOSE AT
OUTPUT SHAFT.3. REMOVE WIPER ARM, RUN WIPER
MOTOR TO PARK POSITION AND
REMOVE THE MODULE. WITHOUT
ROTATING THE MOTOR OUTPUT SHAFT,
REMOVE THE CRANK AND CLEAN ANY
FOREIGN MATTER FROM THE MOTOR
SHAFT. INSTALL THE MOTOR CRANK IN
ITS ORIGINAL POSITION.
4. STRIPPED WIPER ARM HEAD. 4. REPLACE WIPER ARM.
MOTOR STOPS IN ANY
POSITION WHEN THE
SWITCH IS TURNED OFFOPEN PARK CIRCUIT. CHECK PARK SWITCH BY
DISCONNECTING THE WIRE
CONNECTOR AND APPLY BATTERY
VOLTAGE TO PIN 4. PLACE A JUMPER
WIRE FROM PIN 2 TO PIN 3 AND THEN
TO AN EXTERNAL GROUND. REPLACE
MOTOR IF MOTOR DOES NOT PARK.
MOTOR WILL NOT STOP
WHEN THE SWITCH IS
TURNED OFF1. FAULTY SWITCH. 1. CHECK SWITCH IN LOW, HIGH AND
INTERMITTENT POSITION.
2. LACK OF DYNAMIC BRAKE ON
WET GLASS.2. ENSURE PARK SWITCH HAS CLEAN
GROUND.
WIPER BLADES SLAP
AGAINST COWL SCREEN
OR WINDOW MOLDINGS.WIPER ARMS ARE PARKED
INCORRECTLY.PARK WIPER ARMS. REFER TO WIPER
ARM ADJUSTMENT.
BLADES CHATTER 1. FOREIGN SUBSTANCE SUCH
AS POLISH ON GLASS OR
BLADES.1. CLEAN GLASS AND BLADE ELEMENT
WITH NON-ABRASIVE CLEANER.
2. ARMS TWISTED, BLADE AT
WRONG ANGLE ON GLASS.2. REPLACE ARM.
3. BLADE STRUCTURE BENT. 3. REPLACE BLADE.
4. BLADE ELEMENT HAS
PERMANENT SET.4. REPLACE BLADE.
RSWIPERS/WASHERS8R-3
WIPERS/WASHERS (Continued)
(7) Disconnect the wire connectors from back of
the wiper motor.
INSTALLATION
(1) Connect the wire harness connector.
(2) Install the linkage on the wiper unit.
(3) Install the nut holding the linkage to the wiper
unit.
(4) Install the cowl cover brackets to the wiper
nut.
(5) Install the front wiper unit (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(6) Install the cowl cover.
(7) Install the wiper arms and blades.
WIPER MODULE
REMOVAL
(1) Release the hood latch and open hood.
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the wiper arms.
(4) Remove the cowl cover (Refer to 23 - BODY/
EXTERIOR/COWL GRILLE - REMOVAL).
(5) Disconnect the positive lock on the wiper mod-
ule wire connector (Fig. 7).
(6) Disconnect the wiper module wire connector
from the engine compartment wire harness.
(7) Disconnect the windshield washer hose from
coupling outside the module.
(8) Disconnect the drain tubes from nipples on bot-
tom of the wiper module.(9) Remove nuts holding wiper module to lower
windshield fence.
(10) Remove bolts holding the wiper module to the
dash panel (Fig. 8).
(11) Lift wiper module from weld-studs on lower
windshield fence.
CAUTION: Do not allow wiper module to rest on
brake master cylinder reservoir, damage to brake
system can result.
(12) Remove wiper module.
INSTALLATION
(1) Position the wiper module into the cowl.
(2) Install the bolts that secure the wiper module
to the dash (Fig. 8).
(3) Install the nuts that retain the wiper module.
(4) Connect the drain tubes to the nipples on the
wiper module.
(5) Connect the windshield washer tube.
(6) Connect the wire harness connector to the
wiper module (Fig. 8).
(7) Connect the positive lock on the wiper module
wire connector (Fig. 7).
CAUTION: Do not allow wiper module to rest on
brake master cylinder reservoir, damage to brake
system can result.
(8) Install the cowl cover (Refer to 23 - BODY/EX-
TERIOR/COWL GRILLE - INSTALLATION).
(9) Install the wiper arms and blades.
(10) Connect the battery negative cable.
(11) Close the hood.
Fig. 7 WIPER MODULE WIRE CONNECTOR
1 - WIPER SYSTEM WIRE CONNECTOR
2 - LOCK TAB
3 - POSITIVE LOCK
4 - WIPER MODULE
Fig. 8 WIPER MODULE
1 - BOLT
2 - NUTS
3 - BOLT
4 - WIPER MODULE
5 - WINDSHIELD
8R - 14 WIPERS/WASHERSRS
WIPER LINKAGE (Continued)
WIRING
TABLE OF CONTENTS
page page
WIRING DIAGRAM INFORMATION....... 8W-01-1
COMPONENT INDEX.................. 8W-02-1
POWER DISTRIBUTION............... 8W-10-1
GROUND DISTRIBUTION.............. 8W-15-1
BUS COMMUNICATIONS.............. 8W-18-1
CHARGING SYSTEM.................. 8W-20-1
STARTING SYSTEM.................. 8W-21-1
FUEL/IGNITION SYSTEM.............. 8W-30-1
TRANSMISSION CONTROL SYSTEM..... 8W-31-1
VEHICLE SPEED CONTROL............ 8W-33-1
ANTILOCK BRAKES................... 8W-35-1
VEHICLE THEFT SECURITY SYSTEM..... 8W-39-1
INSTRUMENT CLUSTER............... 8W-40-1
HORN/CIGAR LIGHTER/POWER OUTLET . . 8W-41-1
AIR CONDITIONING-HEATER........... 8W-42-1
OCCUPANT RESTRAINT SYSTEM........ 8W-43-1
INTERIOR LIGHTING.................. 8W-44-1
BODY CONTROL MODULE............. 8W-45-1
MESSAGE CENTER................... 8W-46-1
AUDIO SYSTEM..................... 8W-47-1REAR WINDOW DEFOGGER............ 8W-48-1
OVERHEAD CONSOLE................. 8W-49-1
FRONT LIGHTING.................... 8W-50-1
REAR LIGHTING..................... 8W-51-1
TURN SIGNALS...................... 8W-52-1
WIPERS............................ 8W-53-1
TRAILER TOW....................... 8W-54-1
NAVIGATION/TELECOMMUNICATIONS.... 8W-55-1
CONVENIENCE SYSTEMS.............. 8W-56-1
POWER WINDOWS................... 8W-60-1
POWER DOOR LOCKS................ 8W-61-1
POWER MIRRORS................... 8W-62-1
POWER SEATS...................... 8W-63-1
POWER SUNROOF................... 8W-64-1
SPLICE INFORMATION................ 8W-70-1
CONNECTOR PIN-OUTS............... 8W-80-1
CONNECTOR/GROUND/SPLICE
LOCATION........................ 8W-91-1
POWER DISTRIBUTION SYSTEM........ 8W-97-1 RSWIRING
8W-1