2002 JEEP GRAND CHEROKEE key

(8) Install new seals on over drive piston.
(9) Stand transmission case upright on bellhous-
ing.
(10) Position Guide Ring 8114-1 on outer edge of
overdrive piston retainer.
(11) Position Seal Guide 8114-2 on inner edge of
overdrive piston retainer.
(12) Install overdrive piston in overdrive piston
retainer by: aligning locating lugs on overdrive piston
to the two mating holes in retainer.
(a) Aligning locating lugs on overdrive piston to
the two mating holes in retainer.
(b) Lubricate overdrive piston seals with Mopart
Door Ease, or equivalent.
(c) Install piston over Seal Guide 8114-2 and
inside Guide Ring 8114-1.
(d) Push overdrive piston into position in
retainer.
(e) Verify that the locating lugs entered the lug
bores in the retainer.
NOTE: Install the remaining transmission compo-
nents and the overdrive unit.
PARK LOCK CABLE
REMOVAL
(1) Place the shifter in the PARK position.
(2) Lower the steering column cover.
(3) With the ignition switch in the ªRUNº position
depress the park lock cable locking tab, located on
top of the cable connector at the steering column and
pull the park lock cable straight out.
(4) Remove the park lock cable from steering col-
umn (Fig. 197).
(5) Remove the floor console and related trim.
(Refer to 23 - BODY/INTERIOR/FLOOR CONSOLE -
REMOVAL)
(6) Disconnect the park lock cable from the shift
BTSI lever and remove the cable from the shifter
assembly bracket.
(7) Release the park lock cable from any remaining
clips.
(8) Remove park lock cable from the vehicle.
INSTALLATION
NOTE: The gearshift cable must be secured into
position and properly adjusted before the installa-
tion of the Park Lock Cable.
(1) Verify that the shifter is in the PARK position.
(2) Push the park lock cable straight into the
square mounting hole in the steering column until
cable snaps in place.
(3) Route park lock cable to the shifter mecha-
nism.
(4) Install the park lock cable end fitting into
shifter BTSI lever.
(5) Pull rearward on the cable housing to snap
park lock cable adjuster ears into floor shifter
bracket.
(6) Place the ignition key cylinder in the ACCES-
SORY position.
(7) Push the cable adjuster lock clamp downward
to lock it.
(8) Test the park lock cable operation.
(9) Install the floor console and related trim.
(Refer to 23 - BODY/INTERIOR/FLOOR CONSOLE -
INSTALLATION)
Fig. 196 Aligning Overdrive Piston Retainer
1 - PISTON RETAINER
2 - GASKET
3 - RETAINER BOLTS
21 - 108 AUTOMATIC TRANSMISSION - 42REWJ
OVERRUNNING CLUTCH CAM/OVERDRIVE PISTON RETAINER (Continued)

(8) Disengage all wiring connectors from the
shifter assembly.
(9) Remove all nuts holding the shifter assembly to
the floor pan (Fig. 239).
(10) Remove the shifter assembly from the vehicle.
INSTALLATION
(1) Place the floor shifter lever in PARK position.
(2) Loosen the adjustment screw on the shift cable.
(3) Verify that the park lock cable adjustment tab
is pulled upward to the unlocked position.
(4) Install wiring harness to the shifter assembly
bracket. Engage any wire connectors removed from
the shifter assembly.
(5) Install the transfer case shift cable to the
shifter assembly bracket. Install clip to hold cable to
the bracket.
(6) Snap the transfer case shift cable, if equipped,
onto the transfer case shift lever pin.
(7) Install the park lock cable into the shifter
assembly bracket and into the shifter BTSI lever.(Re-
fer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC/SHIFT INTERLOCK MECHANISM -
ADJUSTMENTS)
(8) Install the shift cable to the shifter assembly
bracket. Push cable into the bracket until secure.
(9) Install shifter assembly onto the shifter assem-
bly studs on the floor pan.
(10) Install the nuts to hold the shifter assembly
onto the floor pan. Tighten nuts to 28 N´m (250
in.lbs.).
(11) Snap the shift cable onto the shift lever pin.
(12) Verify that the shift lever is in the PARK posi-
tion.
(13) Tighten the adjustment screw to 7 N´m (65
in.lbs.).
(14) Place the key in the accessory position.(15) Push downward on the park lock cable adjust-
ment tab to lock the adjustment.
(16) Verify correct shifter, park lock, and BTSI
operation.
(17) Install any console parts removed for access to
shift lever assembly and shift cables. (Refer to 23 -
BODY/INTERIOR/FLOOR CONSOLE - INSTALLA-
TION)
SOLENOID
DESCRIPTION
The typical electrical solenoid used in automotive
applications is a linear actuator. It is a device that
produces motion in a straight line. This straight line
motion can be either forward or backward in direc-
tion, and short or long distance.
A solenoid is an electromechanical device that uses
a magnetic force to perform work. It consists of a coil
of wire, wrapped around a magnetic core made from
steel or iron, and a spring loaded, movable plunger,
which performs the work, or straight line motion.
The solenoids used in transmission applications
are attached to valves which can be classified asnor-
mally openornormally closed. Thenormally
opensolenoid valve is defined as a valve which
allows hydraulic flow when no current or voltage is
applied to the solenoid. Thenormally closedsole-
noid valve is defined as a valve which does not allow
hydraulic flow when no current or voltage is applied
to the solenoid. These valves perform hydraulic con-
trol functions for the transmission and must there-
fore be durable and tolerant of dirt particles. For
these reasons, the valves have hardened steel pop-
pets and ball valves. The solenoids operate the valves
directly, which means that the solenoids must have
very high outputs to close the valves against the siz-
able flow areas and line pressures found in current
transmissions. Fast response time is also necessary
to ensure accurate control of the transmission.
The strength of the magnetic field is the primary
force that determines the speed of operation in a par-
ticular solenoid design. A stronger magnetic field will
cause the plunger to move at a greater speed than a
weaker one. There are basically two ways to increase
the force of the magnetic field:
1. Increase the amount of current applied to the
coil or
2. Increase the number of turns of wire in the coil.
The most common practice is to increase the num-
ber of turns by using thin wire that can completely
fill the available space within the solenoid housing.
The strength of the spring and the length of the
plunger also contribute to the response speed possi-
ble by a particular solenoid design.
Fig. 239 Shifter Assembly
1 - FLOOR PAN
2 - SHIFTER ASSEMBLY
WJAUTOMATIC TRANSMISSION - 42RE 21 - 125
SHIFT MECHANISM (Continued)

simultaneous movement without causing the trans-
mission throttle lever to either move ahead of, or lag
behind the lever on the throttle body.
ADJUSTMENT VERIFICATION
(1) Turn ignition key to OFF position.
(2) Remove air cleaner.
(3) Verify that lever on throttle body (Fig. 242) is
at curb idle position. Then verify that the transmis-
sion throttle lever (Fig. 243) is also at idle (fully for-
ward) position.
(4) Slide cable off attachment stud on throttle body
lever.
(5) Compare position of cable end to attachment
stud on throttle body lever:
²Cable end and attachment stud should be
aligned (or centered on one another) to within 1 mm
(0.039 in.) in either direction (Fig. 244).
²If cable end and attachment stud are misaligned
(off center), cable will have to be adjusted as
described in Throttle Valve Cable Adjustment proce-
dure.
(6) Reconnect cable end to attachment stud. Then
with aid of a helper, observe movement of transmis-
sion throttle lever and lever on throttle body.
²If both levers move simultaneously from idle to
half-throttle and back to idle position, adjustment is
correct.
²If transmission throttle lever moves ahead of, or
lags behind throttle body lever, cable adjustment will
be necessary. Or, if throttle body lever prevents
transmission lever from returning to closed position,
cable adjustment will be necessary.
ADJUSTMENT PROCEDURE
(1) Turn ignition switch to OFF position.
(2) Remove air cleaner if necessary.
(3) Disconnect cable end from attachment stud.
Carefully slide cable off stud. Do not pry or pull
cable off.
(4) Verify that transmission throttle lever is in
fully closed position. Then be sure lever on throttle
body is at curb idle position.
(5) Pry the T.V. cable lock (A) into the UP position
(Fig. 244). This will unlock the cable and allow for
readjustment.
(6) Apply just enough tension on the T.V. cable (B)
to remove any slack in the cable.Pulling too tight
will cause the T.V. lever on the transmission to
move out of its idle position, which will result
in an incorrect T.V. cable adjustment.Slide the
sheath of the T.V. cable (D) back and forth until the
centerlines of the T.V. cable end (B) and the throttle
bell crank lever (C) are aligned within one millimeter
(1mm) (Fig. 244).
(7) While holding the T.V. cable in the set position
push the T.V. cable lock (A) into the down position
(Fig. 244). This will lock the present T.V. cable
adjustment.
Fig. 242 Throttle Valve Cable
1 - THROTTLE VALVE CABLE
2 - THROTTLE VALVE LEVER
3 - THROTTLE BODYFig. 243 Throttle Valve Cable at Transmission
1 - TRANSMISSION SHIFTER CABLE
2 - THROTTLE VALVE CABLE
3 - TRANSFER CASE SHIFTER CABLE
4 - TRANSFER CASE SHIFTER CABLE BRACKET RETAINING
BOLT(S)
5 - THROTTLE VALVE CABLE BRACKET RETAINING BOLT
6 - ELECTRICAL CONNECTORS
7 - TRANSMISSION FLUID LINES
WJAUTOMATIC TRANSMISSION - 42RE 21 - 127
THROTTLE VALVE CABLE (Continued)

BRAKE TRANSMISSION SHIFT
INTERLOCK MECHANISM
DESCRIPTION
The Brake Transmission Shifter/Ignition Interlock
(BTSI), is a cable and solenoid operated system. It
interconnects the automatic transmission floor
mounted shifter to the steering column ignition
switch (Fig. 57).
OPERATION
The system locks the shifter into the PARK posi-
tion. The interlock system is engaged whenever the
ignition switch is in the LOCK or ACCESSORY posi-
tion. An additional electrically activated feature will
prevent shifting out of the PARK position unless the
brake pedal is depressed approximately one-half an
inch. A magnetic holding device in the shifter assem-
bly is energized when the ignition is in the RUN
position. When the key is in the RUN position and
the brake pedal is depressed, the shifter is unlocked
and will move into any position. The interlock system
also prevents the ignition switch from being turned
to the LOCK or ACCESSORY position, unless the
shifter is fully locked into the PARK position.
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK
(1) Verify that the key can only be removed in the
PARK position
(2) When the shift lever is in PARK And the shift
handle pushbutton is in the ªOUTº position, the igni-
tion key cylinder should rotate freely from OFF to
LOCK. When the shifter is in any other gear or neu-
tral position, the ignition key cylinder should not
rotate to the LOCK position.
(3) Shifting out of PARK should not be possible
when the ignition key cylinder is in the OFF posi-
tion.
(4) Shifting out of PARK should not be possible
while applying normal pushbutton force and ignition
key cylinder is in the RUN or START positions
unless the foot brake pedal is depressed approxi-
mately 1/2 inch (12mm).
(5) Shifting out of PARK should not be possible
when the ignition key cylinder is in the ACCESSORY
or LOCK positions.
(6) Shifting between any gears, NEUTRAL or into
PARK may be done without depressing foot brake
pedal with ignition switch in RUN or START posi-
tions.
Fig. 57 Ignition Interlock Cable
1 - SHIFT MECHANISM 4 - STEERING COLUMN ASSEMBLY
2 - SHIFTER BTSI LEVER 5 - INTERLOCK CABLE
3 - ADJUSTMENT CLIP
21 - 226 AUTOMATIC TRANSMISSION - 545RFEWJ

ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK
The park interlock cable is part of the brake/shift
lever interlock system. Correct cable adjustment is
important to proper interlock operation. The gear
shift and park lock cables must both be correctly
adjusted in order to shift out of PARK.
ADJUSTMENT PROCEDURE
(1) Remove floor console as necessary for access to
the brake transmission shift interlock cable. (Refer to
23 - BODY/INTERIOR/FLOOR CONSOLE -
REMOVAL)
(2) Shift the transmission into the PARK position.
(3) Turn ignition switch to LOCK position.Be
sure ignition key cylinder is in the LOCK posi-
tion. Cable will not adjust correctly in any
other position.
(4) Pull cable lock button up to release cable (Fig.
58).
(5) Ensure that the cable is free to self-adjust by
pushing cable rearward and releasing.
(6) Push lock button down until it snaps in place.
BTSI FUNCTION CHECK
(1) Verify removal of ignition key allowed in PARK
position only.
(2) When the shift lever is in PARK, and the shift
handle push-button is in the out position, the igni-
tion key cylinder should rotate freely from off to lock.
When the shifter is in any other position, the ignition
key should not rotate from off to lock.
(3) Shifting out of PARK should be possible when
the ignition key cylinder is in the off position.
(4) Shifting out of PARK should not be possible
while applying normal push-button force, and igni-
tion key cylinder is in the run or start positions,
unless the foot brake pedal is depressed approxi-
mately 1/2 inch (12mm).
(5) Shifting out of PARK should not be possible
when the ignition key cylinder is in the accessory or
lock position.
(6) Shifting between any gear and NEUTRAL, or
PARK, may be done without depressing foot brake
with ignition switch in run or start positions.
(7) The floor shifter lever and gate positions
should be in alignment with all transmission detent
positions.
Fig. 58 Brake Transmission Shift Interlock Cable
1 - SHIFT MECHANISM 4 - STEERING COLUMN ASSEMBLY
2 - SHIFTER BTSI LEVER 5 - INTERLOCK CABLE
3 - ADJUSTMENT CLIP
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 227
BRAKE TRANSMISSION SHIFT INTERLOCK MECHANISM (Continued)

OUTPUT SPEED SENSOR
DESCRIPTION
The Input and Output Speed Sensors are two-wire
magnetic pickup devices that generate AC signals as
rotation occurs. They are mounted in the left side of
the transmission case and are considered primary
inputs to the Transmission Control Module (TCM).
OPERATION
The Input Speed Sensor provides information on
how fast the input shaft is rotating. As the teeth of
the input clutch hub pass by the sensor coil, an AC
voltage is generated and sent to the TCM. The TCM
interprets this information as input shaft rpm.
The Output Speed Sensor generates an AC signal
in a similar fashion, though its coil is excited by rota-
tion of the rear planetary carrier lugs. The TCM
interprets this information as output shaft rpm.
The TCM compares the input and output speed
signals to determine the following:
²Transmission gear ratio
²Speed ratio error detection
²CVI calculation
The TCM also compares the input speed signal and
the engine speed signal to determine the following:
²Torque converter clutch slippage
²Torque converter element speed ratio
REMOVAL
(1) Raise vehicle.
(2) Place a suitable fluid catch pan under the
transmission.
(3) Remove the wiring connector from the output
speed sensor (Fig. 96).
(4) Remove the bolt holding the output speed sen-
sor to the transmission case.
(5) Remove the output speed sensor from the
transmission case.
INSTALLATION
(1) Install the output speed sensor into the trans-
mission case.
(2) Install the bolt to hold the output speed sensor
into the transmission case. Tighten the bolt to 11.9
N´m (105 in.lbs.).
(3) Install the wiring connector onto the output
speed sensor
(4) Verify the transmission fluid level. Add fluid as
necessary.
(5) Lower vehicle.
OVERDRIVE SWITCH
DESCRIPTION
The overdrive OFF (control) switch is located in
the shifter handle. The switch is a momentary con-
tact device that signals the PCM to toggle current
status of the overdrive function.
OPERATION
At key-on, fourth and fifth gear operation is
allowed. Pressing the switch once causes the over-
drive OFF mode to be entered and the overdrive OFF
switch lamp to be illuminated. Pressing the switch a
second time causes normal overdrive operation to be
restored and the overdrive lamp to be turned off. The
overdrive OFF mode defaults to ON after the ignition
switch is cycled OFF and ON. The normal position
for the control switch is the ON position. The switch
must be in this position to energize the solenoids and
allow upshifts to fourth and fifth gears. The control
switch indicator light illuminates only when the over-
drive switch is turned to the OFF position, or when
illuminated by the transmission control module.
Fig. 96 Output Speed Sensor
1 - OUTPUT SPEED SENSOR
2 - LINE PRESSURE SENSOR
3 - INPUT SPEED SENSOR
21 - 254 AUTOMATIC TRANSMISSION - 545RFEWJ

PARK LOCK CABLE
REMOVAL
(1) Place the shifter in the PARK position.
(2) Lower the steering column cover.
(3) With the ignition switch in the ªRUNº position
depress the park lock cable locking tab, located on
top of the cable connector at the steering column and
pull the park lock cable straight out.
(4) Remove the park lock cable from steering col-
umn (Fig. 97).
(5) Remove the floor console and related trim.
(Refer to 23 - BODY/INTERIOR/FLOOR CONSOLE -
REMOVAL)
(6) Disconnect the park lock cable from the shift
BTSI lever and remove the cable from the shifter
assembly bracket.
(7) Release the park lock cable from any remaining
clips.
(8) Remove park lock cable from the vehicle.
INSTALLATION
NOTE: The gearshift cable must be secured into
position and properly adjusted before the installa-
tion of the Park Lock Cable.
(1) Verify that the shifter is in the PARK position.
(2) Push the park lock cable straight into the
square mounting hole in the steering column until
cable snaps in place.
(3) Route park lock cable to the shifter mecha-
nism.
(4) Install the park lock cable end fitting into
shifter BTSI lever.
(5) Pull rearward on the cable housing to snap
park lock cable adjuster ears into floor shifter
bracket.
(6) Place the ignition key cylinder in the ACCES-
SORY position.
(7) Push the cable adjuster lock clamp downward
to lock it.
(8) Test the park lock cable operation.
(9) Install the floor console and related trim.
(Refer to 23 - BODY/INTERIOR/FLOOR CONSOLE -
INSTALLATION)
Fig. 97 Brake Transmission Shift Interlock
1 - SHIFT MECHANISM 4 - STEERING COLUMN ASSEMBLY
2 - SHIFTER BTSI LEVER 5 - INTERLOCK CABLE
3 - ADJUSTMENT CLIP
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 255

INSTALLATION
(1) Place the floor shifter lever in PARK position.
(2) Loosen the adjustment screw on the shift cable.
(3) Verify that the park lock cable adjustment tab
is pulled upward to the unlocked position.
(4) Install wiring harness to the shifter assembly
bracket. Engage any wire connectors removed from
the shifter assembly.
(5) Install the transfer case shift cable to the
shifter assembly bracket. Install clip to hold cable to
the bracket.
(6) Snap the transfer case shift cable, if equipped,
onto the transfer case shift lever pin.
(7) Install the park lock cable into the shifter
assembly bracket and into the shifter BTSI lever.(Re-
fer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC/SHIFT INTERLOCK MECHANISM -
ADJUSTMENTS)
(8) Install the shift cable to the shifter assembly
bracket. Push cable into the bracket until secure.
(9) Install shifter assembly onto the shifter assem-
bly studs on the floor pan.
(10) Install the nuts to hold the shifter assembly
onto the floor pan. Tighten nuts to 28 N´m (250
in.lbs.).
(11) Snap the shift cable onto the shift lever pin.
(12) Verify that the shift lever is in the PARK posi-
tion.
(13) Tighten the adjustment screw to 7 N´m (65
in.lbs.).
(14) Place the key in the accessory position.
(15) Push downward on the park lock cable adjust-
ment tab to lock the adjustment.
(16) Verify correct shifter, park lock, and BTSI
operation.
(17) Install any console parts removed for access to
shift lever assembly and shift cables. (Refer to 23 -
BODY/INTERIOR/FLOOR CONSOLE - INSTALLA-
TION)
SOLENOID SWITCH VALVE
DESCRIPTION
The Solenoid Switch Valve (SSV) is located in the
valve body and controls the direction of the transmis-
sion fluid when the L/R-TCC solenoid is energized.
OPERATION
The Solenoid Switch Valve controls line pressure
from the LR-TCC solenoid. In 1st gear, the SSV will
be in the downshifted position, thus directing fluid to
the L/R clutch circuit. In 2nd, 3rd, 4th,and 5th gears,
the solenoid switch valve will be in the upshifted
position and directs the fluid into the torque con-
verter clutch (TCC) circuit.When shifting into 1st gear, a special hydraulic
sequence is performed to ensure SSV movement into
the downshifted position. The L/R pressure switch is
monitored to confirm SSV movement. If the move-
ment is not confirmed (the L/R pressure switch does
not close), 2nd gear is substituted for 1st. A DTC will
be set after three unsuccessful attempts are made to
get into 1st gear in one given key start.
SOLENOIDS
DESCRIPTION
The typical electrical solenoid used in automotive
applications is a linear actuator. It is a device that
produces motion in a straight line. This straight line
motion can be either forward or backward in direc-
tion, and short or long distance.
A solenoid is an electromechanical device that uses
a magnetic force to perform work. It consists of a coil
of wire, wrapped around a magnetic core made from
steel or iron, and a spring loaded, movable plunger,
which performs the work, or straight line motion.
The solenoids used in transmission applications
are attached to valves which can be classified asnor-
mally openornormally closed. Thenormally
opensolenoid valve is defined as a valve which
allows hydraulic flow when no current or voltage is
applied to the solenoid. Thenormally closedsole-
noid valve is defined as a valve which does not allow
hydraulic flow when no current or voltage is applied
to the solenoid. These valves perform hydraulic con-
trol functions for the transmission and must there-
fore be durable and tolerant of dirt particles. For
these reasons, the valves have hardened steel pop-
pets and ball valves. The solenoids operate the valves
directly, which means that the solenoids must have
very high outputs to close the valves against the siz-
able flow areas and line pressures found in current
transmissions. Fast response time is also necessary
to ensure accurate control of the transmission.
The strength of the magnetic field is the primary
force that determines the speed of operation in a par-
ticular solenoid design. A stronger magnetic field will
cause the plunger to move at a greater speed than a
weaker one. There are basically two ways to increase
the force of the magnetic field:
1. Increase the amount of current applied to the
coil or
2. Increase the number of turns of wire in the coil.
The most common practice is to increase the num-
ber of turns by using thin wire that can completely
fill the available space within the solenoid housing.
The strength of the spring and the length of the
plunger also contribute to the response speed possi-
ble by a particular solenoid design.
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 263
SHIFT MECHANISM (Continued)