2001 CHRYSLER VOYAGER tires

²Tires
²Road surfaces
²Wheel bearings
²Engine
²Transmission
²Exhaust
²Propeller shaft (vibration)
²Vehicle body (drumming)
Driveline module noises are normally divided into
two categories: gear noise or bearing noise. A thor-
ough and careful inspection should be completed to
determine the actual source of the noise before
replacing the driveline module.
The rubber mounting bushings help to dampen-out
driveline module noise when properly installed.
Inspect to confirm that no metal contact exists
between the driveline module case and the body. The
complete isolation of noise to one area requires
expertise and experience. Identifying certain types of
vehicle noise baffles even the most capable techni-
cians. Often such practices as:
²Increase tire inflation pressure to eliminate tire
noise.
²Listen for noise at varying speeds with different
driveline load conditions
²Swerving the vehicle from left to right to detect
wheel bearing noise.
All driveline module assemblies produce noise to a
certain extent. Slight carrier noise that is noticeable
only at certain speeds or isolated situations should be
considered normal. Carrier noise tends to peak at a
variety of vehicle speeds. Noise isNOT ALWAYSan
indication of a problem within the carrier.
TIRE NOISE
Tire noise is often mistaken for driveline module
noise. Tires that are unbalanced, worn unevenly or
are worn in a saw-tooth manner are usually noisy.
They often produce a noise that appears to originate
in the driveline module.
Tire noise changes with different road surfaces, but
driveline module noise does not. Inflate all four tires
with approximately 20 psi (138 kPa) more than the
recommended inflation pressure (for test purposes
only). This will alter noise caused by tires, but will
not affect noise caused by the differential. Rear axle
noise usually ceases when coasting at speeds less
than 30 mph (48 km/h); however, tire noise contin-
ues, but at a lower frequency, as the speed is
reduced.
After test has been completed lower tire pressure
back to recommended pressure.
GEAR NOISE (DRIVE PINION AND RING GEAR)
Abnormal gear noise is rare and is usually caused
by scoring on the ring gear and drive pinion. Scoringis the result of insufficient or incorrect lubricant in
the carrier housing.
Abnormal gear noise can be easily recognized. It
produces a cycling tone that will be very pronounced
within a given speed range. The noise can occur dur-
ing one or more of the following drive conditions:
²Drive
²Road load
²Float
²Coast
Abnormal gear noise usually tends to peak within
a narrow vehicle speed range or ranges. It is usually
more pronounced between 30 to 40 mph (48 to 64
km/h) and 50 to 60 mph (80 to 96 km/h). When objec-
tionable gear noise occurs, note the driving condi-
tions and the speed range.
BEARING NOISE (DRIVE PINION AND
DIFFERENTIAL)
Defective bearings produce a rough growl that is
constant in pitch and varies with the speed of vehi-
cle. Being aware of this will enable a technician to
separate bearing noise from gear noise.
Drive pinion bearing noise that results from defec-
tive or damaged bearings can usually be identified by
its constant, rough sound. Drive pinion front bearing
is usually more pronounced during a coast condition.
Drive pinion rear bearing noise is more pronounced
during a drive condition. The drive pinion bearings
are rotating at a higher rate of speed than either the
differential side bearings or the axle shaft bearing.
Differential side bearing noise will usually produce
a constant, rough sound. The sound is much lower in
frequency than the noise caused by drive pinion bear-
ings.
Bearing noise can best be detected by road testing
the vehicle on a smooth road (black top). However, it
is easy to mistake tire noise for bearing noise. If a
doubt exists, the tire treads should be examined for
irregularities that often causes a noise that resem-
bles bearing noise.
ENGINE AND TRANSMISSION NOISE
Sometimes noise that appears to be in the driv-
eline module assembly is actually caused by the
engine or the transmission. To identify the true
source of the noise, note the approximate vehicle
speed and/or RPM when the noise is most noticeable.
Stop the vehicle next to a flat brick or cement wall
(this will help reflect the sound). Place the transaxle
inNEUTRAL. Accelerate the engine slowly up
through the engine speed that matches the vehicle
speed noted when the noise occurred. If the same
noise is produced, it usually indicates that the noise
is being caused by the engine or transaxle.
3 - 28 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)

DIAGNOSIS AND TESTING - REAR DRIVELINE
MODULE OPERATION
Driveline module operation requires relatively
straight-forward diagnosis. Refer to the following
chart:
DRIVELINE MODULE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
Rear wheels not
overrunning1) Bi-directional overrunning clutch
failure1) Replace overrunning clutch
components as required
No AWD in forward or
reverse directions, propeller
shaft turning1) Bi-directional overrunning clutch
failure1) Replace overrunning clutch
components as required
2) Viscous coupling failure 2) Replace viscous coupling
3) Rear differential failure 3) Replace the rear differential
assembly
No AWD in forward or
reverse directions, propeller
shaft not turning1) Power transfer unit failure. 1) Replace power transfer unit
components as necessary
Vibration at all speeds,
continuous torque transfer1) Mis-matched tires, worn tires on
front axle.1) Replace worn or incorrect
(mis-matched) tires with same
make and size
REMOVAL
(1) Raise vehicle on hoist.
(2) Drain fluid from overrunning clutch housing
and/or differential assembly if necessary.
(3) Remove propeller shaft. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/PROPELLER SHAFT -
REMOVAL)
(4) Disconnect left and right rear halfshafts from
output flanges (Fig. 2).(5) Remove torque arm mount to body bolts.
(6) Position transmission jack to driveline module
assembly and secure assembly to jack.
(7) Remove two driveline module-to-body bolts
(Fig. 3).
(8) Lower driveline module from vehicle and
remove from jack.
Fig. 2 Half Shaft Mounting Bolts
1 - SHAFT
2 - FLANGE
Fig. 3 Rear Drive Line Module Assembly Mounting
Bolts
1 - DRIVELINE MODULE RETAINING BOLT (2)
2 - RUBBER ISOLATOR
3 - WASHER
RSREAR DRIVELINE MODULE3-29
REAR DRIVELINE MODULE (Continued)

DIFFERENTIAL ASSEMBLY
DESCRIPTION
The differential gear system divides the torque
between the axle shafts. It allows the axle shafts to
rotate at different speeds when turning corners.
Each differential side gear is splined to an axle
shaft. The pinion gears are mounted on a pinion
mate shaft and are free to rotate on the shaft. The
pinion gear is fitted in a bore in the differential case
and is positioned at a right angle to the axle shafts.
OPERATION
In operation, power flow occurs as follows:
²The pinion gear rotates the ring gear
²The ring gear (bolted to the differential case)
rotates the case
²The differential pinion gears (mounted on the
pinion mate shaft in the case) rotate the side gears
²The side gears (splined to the axle shafts) rotate
the shafts
During straight-ahead driving, the differential pin-
ion gears do not rotate on the pinion mate shaft. This
occurs because input torque applied to the gears is
divided and distributed equally between the two side
gears. As a result, the pinion gears revolve with the
pinion mate shaft but do not rotate around it (Fig.
38).When turning corners, the outside wheel must
travel a greater distance than the inside wheel to
complete a turn. The difference must be compensated
for to prevent the tires from scuffing and skidding
through turns. To accomplish this, the differential
allows the axle shafts to turn at unequal speeds (Fig.
39). In this instance, the input torque applied to the
pinion gears is not divided equally. The pinion gears
now rotate around the pinion mate shaft in opposite
directions. This allows the side gear and axle shaft
attached to the outside wheel to rotate at a faster
speed.
Fig. 37 BOC Input Shaft
1 - GROOVED AREA (2 LOCATIONS)
2 - ROLLER MATING SURFACE
Fig. 38 Differential OperationÐStraight Ahead
Driving
1 - IN STRAIGHT AHEAD DRIVING EACH WHEEL ROTATES AT
100% OF CASE SPEED
2 - PINION GEAR
3 - SIDE GEAR
4 - PINION GEARS ROTATE WITH CASE
Fig. 39 Differential OperationÐOn Turns
1 - PINION GEARS ROTATE ON PINION SHAFT
RSREAR DRIVELINE MODULE3-43
BI-DIRECTIONAL OVERRUNNING CLUTCH (Continued)

Schedule Condition Expected Operation
HotOil temperature at start-up above
80É F± Normal operation (upshift,
kickdowns, and coastdowns)
± Full EMCC, no PEMCC except to
engage FEMCC (except at closed
throttle at speeds above 70-83 mph)
OverheatOil temperature above 240É F or
engine coolant temperature above
244É F± Delayed 2-3 upshift (25-32 mph)
± Delayed 3-4 upshift (41-48 mph)
± 3rd gear FEMCC from 30-48 mph
± 3rd gear PEMCC from 27-31 mph
Super OverheatOil temperature above 260É F ± All9Overheat9shift schedule
features apply
± 2nd gear PEMCC above 22 mph
± Above 22 mph the torque
converter will not unlock unless the
throttle is closed or if a wide open
throttle 2nd PEMCC to 1 kickdown
is made
STANDARD PROCEDURE - PINION FACTOR
SETTING
NOTE: This procedure must be performed if the
Transmission Control Module (TCM) has been
replaced with a NEW or replacement unit. Failure to
perform this procedure will result in an inoperative
or improperly calibrated speedometer.
The vehicle speed readings for the speedometer are
taken from the output speed sensor. The TCM must
be calibrated to the different combinations of equip-
ment (final drive and tires) available. Pinion Factor
allows the technician to set the Transmission Control
Module initial setting so that the speedometer read-
ings will be correct. To properly read and/or reset the
Pinion Factor, it is necessary to use a DRB scan tool.
(1) Plug the DRB scan tool into the diagnostic con-
nector located under the instrument panel.
(2) Select the Transmission menu.
(3) Select the Miscellaneous menu.
(4) Select Pinion Factor. Then follow the instruc-
tions on the DRB scan tool screen.
STANDARD PROCEDURE - QUICK LEARN
PROCEDURE
The quick learn procedure requires the use of the
DRB scan tool. This program allows the electronic
transaxle system to recalibrate itself. This will pro-
vide the best possible transaxle operation.NOTE: The quick learn procedure should be per-
formed if any of the following procedures are per-
formed:
²Transaxle Assembly Replacement
²Transmission Control Module Replacement
²Solenoid/Pressure Switch Assembly Replacement
²Clutch Plate and/or Seal Replacement
²Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the follow-
ing conditions must be met:
²The brakes must be applied
²The engine speed must be above 500 rpm
²The throttle angle (TPS) must be less than 3
degrees
²The shift lever position must stay until
prompted to shift to overdrive
²The shift lever position must stay in overdrive
after the Shift to Overdrive prompt until the DRB
indicates the procedure is complete
²The calculated oil temperature must be above
60É and below 200É
(1) Plug the DRB scan tool into the diagnostic con-
nector. The connector is located under the instrument
panel.
(2) Go to the Transmission screen.
(3) Go to the Miscellaneous screen.
(4) Select Quick Learn Procedure. Follow the
instructions of the DRB to perform the Quick Learn
Procedure.
RSELECTRONIC CONTROL MODULES8E-27
TRANSMISSION CONTROL MODULE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
SPEEDOMETER
INACCURATE.1. SPEEDOMETER OUT
OF CALIBRATION.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST.
²IF SPEEDOMETER IS ACCURATE TO THE
CALIBRATION POINTS THEN LOOK FOR ANOTHER
POSSIBLE CAUSE OF INACCURACY.
²IF SPEEDOMETER IS NOT ACCURATE TO THE
CALIBRATION POINTS, REPLACE CLUSTER
ASSEMBLY.
2. WRONG
SPEEDOMETER PINION
SIZE FOR TIRE SIZE.2.A. IF VEHICLE HAS A 4 SPEED ELECTRONIC
TRANSMISSION GO TO STEP 2.C. OTHERWISE GO
TO STEP 2.B.
2.B. CHECK IF CORRECT SPEEDOMETER PINION
IS BEING USED WITH TIRES ON VEHICLE. REFER
TO TRANSMISSION FOR DIAGNOSIS AND
TESTING.
²IF THE INCORRECT PINION IS IN TRANSMISSION
THEN REPLACE WITH CORRECT PINION.
²IF THE CORRECT PINION IS IN THE
TRANSMISSION, CHECK TIRE SIZE.
2.C. USE A DRB IIITSCAN TOOL TO CHECK THE
TCM TO SEE IF THE CORRECT TIRE SIZE HAS
BEEN PROGRAMMED INTO THE TCM.
²IF THE INCORRECT TIRE SIZE WAS SELECTED,
SELECT THE PROPER TIRE SIZE.
²IF THE CORRECT TIRE SIZE WAS SELECTED,
CHECK SPEED SENSOR.
3. BAD SPEED SENSOR. 3. REFER TO TRANSMISSION, SPEED SENSOR,
DIAGNOSIS AND TESTING.
TACHOMETER DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO POINTER
MOVEMENT1. INTERNAL
CLUSTER FAILURE.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST AND
CHECK FOR FAULT CODES.
²IF TACHOMETER POINTER MOVES TO CALIBRATION
POINTS DURING TEST, LOOK FOR ANOTHER
POSSIBLE CAUSE OF FAILURE.
²
IF THE POINTER DOESN'T MOVE DURING TEST,
CHECK FOR POWER AND GROUND TO THE MIC.
IF POWER AND GROUND ARE PRESENT GO TO
STEP 1.B.
1.B. REPLACE CLUSTER. GO TO STEP 1.C.
2.9NO RPM9PCI BUS
MESSAGE OR9ZERO
RPM9PCI BUS
MESSAGE FROM
PCM.2. CHECK THE PCM USING A DRB IIITSCAN TOOL.
REFER TO THE PROPER ENGINE DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE AND
REPAIR.
8J - 6 INSTRUMENT CLUSTERRS
INSTRUMENT CLUSTER (Continued)

AIRBAG SQUIB STATUS
(1) Using a DRBIIItread Airbag DTC's
Ifthe following active codes are present:
DTC CONDITIONS ACTIVE SQUIB
Driver Squib 1 openAND IFthe stored minutes for both are within 15
minutes of each other, both Driver Squib 1 and 2 were
used.Both Driver Squib 1 and
2 were used.
Driver Squib 2 open
Driver Squib 1 openAND IFthe stored minutes for Driver Squib 2 open is
GREATER than the stored minutes for Driver Squib 1
by 15 minutes or more.Driver Squib 1 was used;
Driver Squib 2 is live.
Driver Squib 2 open
Driver Squib 1 openAND IFthe stored minutes for Driver Squib 1 open is
GREATER than the stored minutes for Driver Squib 2
by 15 minutes or more.Driver Squib 1 is live;
Driver Squib 2 was used.
Driver Squib 2 open
IfDriver Squib 1 open is
an active codeAND IFDriver Squib 2 open is NOT an active code.Driver Squib 1 was used;
Driver Squib 2 is live.
IfDriver Squib 2 open is
an active codeAND IFDriver Squib 1 open is NOT an active code.Driver Squib 1 is live;
Driver Squib 2 was used.
Ifneither of the following codes is an active code:
DTC ACTIVE SQUIB
Driver squib 1 open
Status of Airbag is
Unknown.
Driver squib 2 open
NOTE: If the Driver/Passenger Airbag is defective
and not deployed, refer to DaimlerChrysler Motors
Corporation current return policies for proper han-
dling procedures.
DIAGNOSIS AND TESTING - AIRBAG SYSTEM
(1) Connect a DRBIIItscan tool to the Data Link
Connector (DLC), located at left side of the steering
column and at the lower edge of the lower instru-
ment panel.
(2) Turn the ignition key to ON position. Exit vehi-
cle with scan tool. Use the latest version of the
proper cartridge.
(3) After checking that no one is inside the vehicle,
connect the battery negative terminal.
(4) Using the DRBIIItscan tool, read and record
active diagnostic code data.
(5) Read and record any stored diagnostic codes.
(6) Refer to the proper Body Diagnostic Procedures
manual if any diagnostic codes are found in Step 4 or
Step 5.
(7) Erase stored diagnostic codes if there are no
active diagnostic codes. If problems remain, diagnos-
tic codes will not erase. Refer to the Proper Body
Diagnostic Procedures Manual to diagnose the prob-
lem.If airbag warning lamp either fails to light,
or goes on and stays on, there is a system mal-function. Refer to the proper Body Diagnostic
Procedures manual to diagnose the problem.
CLOCK SPRING
DESCRIPTION
The clock spring is screwed to a plastic mounting
platform on the steering column behind the steering
wheel. The clock spring is used to maintain a contin-
uous electrical circuit between the wiring harness
and the drivers airbag.
OPERATION
This assembly consists of a flat ribbon like electri-
cally conductive tape which winds and unwinds with
the steering wheel rotation. The clock spring cannot
be repaired. If the clock spring is faulty, damaged, or
if the airbag has been deployed, the clock spring
must be replaced.
STANDARD PROCEDURE - CLOCK SPRING
CENTERING
If the rotating tape (wire coil) in the clock spring is
not positioned properly with the steering wheel and
the front wheels, the clock spring may fail. The fol-
lowing procedure MUST BE USED to center the
clock spring if it is not known to be properly posi-
tioned, or if the front wheels were moved from the
straight ahead position.
(1) Adjust the steering wheel so that the tires are
in a straight ahead position.
(2) Remove Driver Airbag from steering wheel.
(3) Disconnect wire connectors from back of airbag.
RSRESTRAINTS8O-3
RESTRAINTS (Continued)

The components above must be replaced because
they cannot be reused. Replace any other driver air-
bag system components if damaged.
REMOVAL
DEPLOYED AIRBAG
The Driver Airbag and Driver Airbag Cover/Horn
Pad are serviced separately from each other.
(1) Clean powder residue from interior of vehicle,
(Refer to 8 - ELECTRICAL/RESTRAINTS/DRIVER
AIRBAG - STANDARD PROCEDURE ) Cleanup.
(2) Remove two screws attaching Driver Airbag to
steering wheel.
(3) Remove the driver airbag from steering wheel.
(4) Disconnect wire connectors from Airbag and
Clock Spring.
(5) Adjust the steering wheel so that the tires are
in a straight ahead position. Remove steering wheel,
(Refer to 19 - STEERING/COLUMN/STEERING
WHEEL - REMOVAL)
(6) Disconnect the 2-way and 4-way connectors
between the clock spring and the instrument panel
wiring harness.
(7) Remove upper and lower steering column
shrouds.
(8) Remove clock spring from the housing assem-
bly by depressing the 2 tabs on the clock spring.
UNDEPLOYED AIRBAG
(1) Remove screws attaching airbag/horn switch to
steering wheel.
(2) Remove Driver Airbag from steering wheel.
(3) Disconnect wire connectors from driver airbag
and clock spring.
INSTALLATION
DEPLOYED AIRBAG
(1) Perform cleanup procedure.(Refer to 8 - ELEC-
TRICAL/RESTRAINTS/DRIVER AIRBAG - STAN-
DARD PROCEDURE)
(2) Install a new steering column assembly and
lower steering column coupler. Refer to Steering, Col-
umn, Installation.
(3) Install the clock spring.
(4) Install the driver airbag and the two screws
retaining the airbag. Tighten screws to 10 N´m (90
in. lbs.)
WARNING: DO NOT CONNECT THE BATTERY NEGA-
TIVE CABLE. REFER TO ELECTRICAL, RESTRAINTS,
DIAGNOSIS AND TESTING - AIRBAG SYSTEM FIRST.
UNDEPLOYED AIRBAG
(1) Position a new airbag into the airbag cavity.(2) Install the two screws retaining the airbag.
Tighten screws to 10 N´m (90 in. lbs.)
WARNING: DO NOT CONNECT THE BATTERY NEGA-
TIVE CABLE. REFER TO ELECTRICAL, RESTRAINTS,
DIAGNOSIS AND TESTING - AIRBAG SYSTEM FIRST.
OCCUPANT RESTRAINT
CONTROLLER
DESCRIPTION
The front driver and passenger airbag system is
designed to reduce the risk of fatality or serious
injury, caused by a frontal impact of the vehicle.
The Occupant Restraint Controller (ORC) contains
the impact sensor and energy reserve capacitor. It is
mounted on a bracket, under the instrument panel,
just forward of the storage bin. The ORC monitors
the system to determine the system readiness. The
ORC contains on-board diagnostics and will light the
AIRBAG warning lamp in the message center when a
problem occurs.
OPERATION
The impact sensor provides verification of the
direction and severity of the impact. One impact sen-
sor is used. It is located inside the Occupant
Restraint Controller (ORC). The impact sensor is an
accelerometer that senses deceleration. The decelera-
tion pulses are sent to a microprocessor which con-
tains a decision algorithm. When an impact is severe
enough to require airbag protection, the ORC micro-
processor sends a signal that completes the electrical
circuit to the driver and passenger airbags. The
impact sensor is calibrated for the specific vehicle
and reacts to the severity and direction of an impact.
REMOVAL
(1)Disconnect and isolate the battery negative cable.
(2) Remove storage bin from instrument panel.
Refer to Body, Instrument Panel, Storage Bin,
Removal.
(3) Remove three bolts holding ORC to floor
bracket.
(4) Disconnect the wire connector from ORC.
(5) Remove the ORC w/bracket assembly from
vehicle.
INSTALLATION
WARNING: DO NOT INSTALL ORC IF MOUNTING
LOCATION IS DEFORMED OR DAMAGED.
RSRESTRAINTS8O-5
DRIVER AIRBAG (Continued)

²A rapid increase rpm (indicates that the clutch
has been disengaged)
²Excessive engine rpm (indicates that the trans-
mission may be in a low gear)
²The speed signal increases at a rate of 10 mph
per second (indicates that the co-efficient of friction
between the road surface and tires is extremely low)
²The speed signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
²If the actual speed is not within 20 mph of the
set speed. The previous disengagement conditions are
programmed for added safety.
Once the speed control has been disengaged,
depressing the RESUME switch when speed is
greater than 25 mph allows the vehicle to resume
control to the target speed that was stored in the
PCM.
While the speed control is engaged, the driver can
increase the vehicle speed by depressing the ACCEL
switch. The new target speed is stored in the PCM
when the ACCEL switch is released. The PCM also
has a9tap-up9feature in which target speed
increases by 2 mph for each momentary switch acti-
vation of the ACCEL switch. The PCM also provides
a means to decelerate to a new lower target speed
without disengaging speed control. Depress and hold
the COAST switch until the desired speed is reached,
then release the switch.
The PCM also has a ªTap Downº feature in which
target speed decreases at 1 mph for each momentary
switch activation of the coast switch.
OPERATION - INTERACTIVE SPEED CONTROL
(4 Speed EATX Only)
Interactive means that communication between the
PCM and the TCM is taking place. Interactive speed
control avoids unnecessary shifting for smoother, qui-
eter operation and when downshifts are required,
makes the shifts smoother.
CLIMBING A GRADE
DESCRIPTION
When climbing a grade the interactive speed con-
trol tries to maintain the set speed by increasing the
throttle opening, while inability/delaying downshifts.
OPERATION
If opening the throttle alone cannot maintain the
set speed and the vehicle speed drops more than three
mph below the set speed, the transmission will down-
shift to third gear. If the vehicle continues to lose
speed, by more than 6 mph, the transmission will
downshift again to maintain the set speed. After the
vehicle encounters a less-steep grade, or has crestedthe grade (reduced the load on the powertrain) and
can maintain the set speed at a reduced throttle posi-
tion, the transmission will upshift, as appropriate,
until the set speed can be maintained in Overdrive.
GRADE HUNTING
DESCRIPTION
All vehicles equipped with a four speed automatic
transmission have a grade hunting feature for the 2nd
to 3rd gear upshift and the 3rd to Overdrive upshift.
OPERATION
The TCM identifies the powertrain loading condi-
tions and selects the proper gear to maintain the cur-
rent vehicle speed. Under moderate loading
conditions the transaxle will stay in 3rd gear until
the top of the grade is reached or the powertrain
loading is reduced.
If powertrain loading is severe, the transaxle may
shift into 2nd gear and remain there until power-
train loading is reduced, then a 2nd to 3rd gear
upshift will be scheduled. Grade hunting features
always operate regardless of whether or not the
interactive speed control is engaged.If the interac-
tive speed control is not engaged and power-
train loading is not reduced, the driver may
have to completely lift off of the throttle before
an upshift will occur. If the driver does lift off the
throttle to induce an upshift under these conditions,
vehicle speed will reduce and the Overdrive to 3rd
and 3rd to 2nd gear downshifts will reoccur when the
throttle is reapplied. If grade hunting is repeatedly
induced by the driver, transaxle damage may result.
AUTOMATIC SPEED CONTROL OVERSPEED
REDUCTION
DESCRIPTION
Transmission control software includes an auto-
matic speed control overspeed reduction feature. This
maintains vehicle speed at the selected set point
when descending a grade.
OPERATION
The Transmission Control Module (TCM) 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 TCM causes the transaxle to
downshift to THIRD gear. After downshifting, the
automatic speed control resumes normal operation.
To ensure that an upshift is appropriate after the set
speed is reached, the TCM waits until the speed con-
trol system opens the throttle at least 6 degrees
before upshifting to OVERDRIVE again.
8P - 2 SPEED CONTROLRS
SPEED CONTROL (Continued)