2002 JEEP GRAND CHEROKEE lock

Replace the driving shell if worn, cracked or dam-
aged.
Replace planetary gear sets if gears, pinion pins, or
carrier are damaged in any way. Replace the annulus
gears and supports if either component is worn or
damaged.
Replace the output shaft if the machined surfaces
are scored, pitted, or damaged in any way. Also
replace the shaft if the splines are damaged, or
exhibits cracks at any location.
ASSEMBLY
(1) Clean and inspect all components. Replace any
components which show evidence of excessive wear
or scoring.
(2) Install the number 11 bearing into the input
planetary carrier so that the inner race will be
toward the front of the transmission (Fig. 104).
(3) Install the input sun gear into the input carrier
(Fig. 104).
(4) Install the number 10 bearing onto the rear of
the reverse planetary carrier with the inner race
toward the carrier (Fig. 104).
(5) Install the number 9 bearing onto the front of
the reverse planetary carrier with the outer race
toward the carrier and the inner race facing upward
(Fig. 104).
(6) Install the reverse planetary gear carrier into
the input carrier (Fig. 104).
(7) Install the input annulus gear into the input
carrier (Fig. 104).
(8) Install the snap-ring to hold the input annulus
gear into the input carrier (Fig. 104).
SHIFT MECHANISM
DESCRIPTION
The gear shift mechanism provides six shift posi-
tions which are:
²Park (P)
²Reverse (R)
²Neutral (N)
²Drive (D)
²Manual second (2)
²Manual low (1)
OPERATION
MANUAL LOW (1) range provides FIRST gear
only. Overrun braking is also provided in this range.
MANUAL SECOND (2) range provides FIRST and
SECOND gear only.
DRIVE range provides FIRST, SECOND, THIRD
and OVERDRIVE FOURTH and FIFTH gear ranges.
The shift into OVERDRIVE FOURTH and FIFTH
gear range occurs only after the transmission hascompleted the shift into D THIRD gear range. No
further movement of the shift mechanism is required
to complete the 3-4 or 4-5 shifts.
The FOURTH and FIFTH gear upshifts occurs
automatically when the overdrive selector switch is
in the ON position. An upshift to FOURTH and
FIFTH gears may not occur or may be delayed in
some of the possible shift schedules. (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/TRANSMISSION CONTROL MODULE -
OPERATION)
REMOVAL
(1) Remove any necessary console parts for access
to shift lever assembly and shifter cables. (Refer to
23 - BODY/INTERIOR/FLOOR CONSOLE -
REMOVAL)
(2) Shift transmission into PARK.
(3) Disconnect the transmission shift cable at shift
lever and shifter assembly bracket (Fig. 105).
(4) Disconnect the park lock cable from the shifter
BTSI lever and the shifter assembly bracket. (Fig.
106)
(5) Disconnect the transfer case shift cable from
the transfer case shift lever pin (Fig. 107), if
equipped.
(6) Remove the clip holding the transfer case shift
cable to the shifter assembly bracket, if equipped.
(7) Remove the transfer case shift cable from the
shifter assembly bracket, if equipped.
(8) Disengage all wiring connectors from the
shifter assembly.
(9) Remove all nuts holding the shifter assembly to
the floor pan (Fig. 108).
Fig. 105 Transmission Shift Cable
1 - SHIFT LEVER PIN
2 - ADJUSTMENT SCREW
3 - SHIFT CABLE
4 - SHIFTER ASSEMBLY BRACKET
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 261
PLANETARY GEARTRAIN (Continued)

(10) Remove the shifter assembly from the vehicle.
Fig. 106 Brake Transmission Interlock Cable
1 - SHIFT MECHANISM 4 - STEERING COLUMN ASSEMBLY
2 - SHIFTER BTSI LEVER 5 - INTERLOCK CABLE
3 - ADJUSTMENT CLIP
Fig. 107 Transfer Case Shift Cable
1 - CLIP
2 - SHIFTER
3 - TRANSFER CASE SHIFT LEVER PIN
4 - TRANSFER CASE SHIFT CABLE
Fig. 108 Shifter Assembly
1 - FLOOR PAN
2 - SHIFTER ASSEMBLY
21 - 262 AUTOMATIC TRANSMISSION - 545RFEWJ
SHIFT MECHANISM (Continued)

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)

STATOR
The stator assembly (Fig. 112) is mounted on a sta-
tionary shaft which is an integral part of the oil
pump. The stator is located between the impeller and
turbine within the torque converter case (Fig. 113).
The stator contains an over-running clutch, which
allows the stator to rotate only in a clockwise direc-
tion. When the stator is locked against the over-run-
ning clutch, the torque multiplication feature of the
torque converter is operational.
TORQUE CONVERTER CLUTCH (TCC)
The TCC (Fig. 114) was installed to improve the
efficiency of the torque converter that is lost to the
slippage of the fluid coupling. Although the fluid cou-
pling provides smooth, shock-free power transfer, it is
natural for all fluid couplings to slip. If the impeller
and turbine were mechanically locked together, a
zero slippage condition could be obtained. A hydraulic
piston with friction material was added to the tur-
bine assembly to provide this mechanical lock-up.
In order to reduce heat build-up in the transmission
and buffer the powertrain against torsional vibrations,
the TCM can duty cycle the L/R-CC Solenoid to achieve
a smooth application of the torque converter clutch.
This function, referred to as Electronically Modulated
Converter Clutch (EMCC) can occur at various times
depending on the following variables:
²Shift lever position
²Current gear range
²Transmission fluid temperature
²Engine coolant temperature
²Input speed
²Throttle angle
²Engine speed
Fig. 112 Stator Components
1 - CAM (OUTER RACE)
2 - ROLLER
3 - SPRING
4 - INNER RACE
Fig. 113 Stator Location
1-STATOR
2 - IMPELLER
3 - FLUID FLOW
4 - TURBINE
Fig. 114 Torque Converter Clutch (TCC)
1 - IMPELLER FRONT COVER
2 - THRUST WASHER ASSEMBLY
3 - IMPELLER
4-STATOR
5 - TURBINE
6 - PISTON
7 - FRICTION DISC
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 267
TORQUE CONVERTER (Continued)

OPERATION
The converter impeller (Fig. 115) (driving member),
which is integral to the converter housing and bolted
to the engine drive plate, rotates at engine speed.
The converter turbine (driven member), which reacts
from fluid pressure generated by the impeller, rotates
and turns the transmission input shaft.
TURBINE
As the fluid that was put into motion by the impel-
ler blades strikes the blades of the turbine, some of
the energy and rotational force is transferred into the
turbine and the input shaft. This causes both of them
(turbine and input shaft) to rotate in a clockwise
direction following the impeller. As the fluid is leav-
ing the trailing edges of the turbine's blades it con-
tinues in a ªhinderingº direction back toward the
impeller. If the fluid is not redirected before it strikes
the impeller, it will strike the impeller in such a
direction that it would tend to slow it down.
STATOR
Torque multiplication is achieved by locking the
stator's over-running clutch to its shaft (Fig. 116).
Under stall conditions (the turbine is stationary), the
oil leaving the turbine blades strikes the face of the
stator blades and tries to rotate them in a counter-
clockwise direction. When this happens the over-run-ning clutch of the stator locks and holds the stator
from rotating. With the stator locked, the oil strikes
the stator blades and is redirected into a ªhelpingº
direction before it enters the impeller. This circula-
tion of oil from impeller to turbine, turbine to stator,
and stator to impeller, can produce a maximum
torque multiplication of about 2.4:1. As the turbine
begins to match the speed of the impeller, the fluid
that was hitting the stator in such as way as to
cause it to lock-up is no longer doing so. In this con-
dition of operation, the stator begins to free wheel
and the converter acts as a fluid coupling.
TORQUE CONVERTER CLUTCH (TCC)
In a standard torque converter, the impeller and
turbine are rotating at about the same speed and the
stator is freewheeling, providing no torque multipli-
cation. By applying the turbine's piston and friction
material to the front cover, a total converter engage-
ment can be obtained. The result of this engagement
is a direct 1:1 mechanical link between the engine
and the transmission.
The clutch can be engaged in second, third, fourth,
and fifth gear ranges depending on overdrive control
switch position. If the overdrive control switch is in
the normal ON position, the clutch will engage after
the shift to fourth gear, and above approximately 72
km/h (45 mph). If the control switch is in the OFF
Fig. 115 Torque Converter Fluid Operation - Typical
1 - APPLY PRESSURE 3 - RELEASE PRESSURE
2 - THE PISTON MOVES SLIGHTLY FORWARD 4 - THE PISTON MOVES SLIGHTLY REARWARD
21 - 268 AUTOMATIC TRANSMISSION - 545RFEWJ
TORQUE CONVERTER (Continued)

position, the clutch will engage after the shift to
third gear, at approximately 56 km/h (35 mph) at
light throttle.
The TCM controls the torque converter by way of
internal logic software. The programming of the soft-
ware provides the TCM with control over the L/R-CC
Solenoid. There are four output logic states that can
be applied as follows:
²No EMCC
²Partial EMCC
²Full EMCC
²Gradual-to-no EMCC
NO EMCC
Under No EMCC conditions, the L/R Solenoid is
OFF. There are several conditions that can result in
NO EMCC operations. No EMCC can be initiated
due to a fault in the transmission or because the
TCM does not see the need for EMCC under current
driving conditions.
PARTIAL EMCC
Partial EMCC operation modulates the L/R Sole-
noid (duty cycle) to obtain partial torque converter
clutch application. Partial EMCC operation is main-
tained until Full EMCC is called for and actuated.
During Partial EMCC some slip does occur. Partial
EMCC will usually occur at low speeds, low load and
light throttle situations.
FULL EMCC
During Full EMCC operation, the TCM increases
the L/R Solenoid duty cycle to full ON after PartialEMCC control brings the engine speed within the
desired slip range of transmission input speed rela-
tive to engine rpm.
GRADUAL-TO-NO EMCC
This operation is to soften the change from Full or
Partial EMCC to No EMCC. This is done at mid-
throttle by decreasing the L/R Solenoid duty cycle.
REMOVAL
(1) Remove transmission and torque converter
from vehicle.
(2) Place a suitable drain pan under the converter
housing end of the transmission.
CAUTION: Verify that transmission is secure on the
lifting device or work surface, the center of gravity
of the transmission will shift when the torque con-
verter is removed creating an unstable condition.
The torque converter is a heavy unit. Use caution
when separating the torque converter from the
transmission.
(3) Pull the torque converter forward until the cen-
ter hub clears the oil pump seal.
(4) Separate the torque converter from the trans-
mission.
INSTALLATION
Check converter hub and drive flats for sharp
edges, burrs, scratches, or nicks. Polish the hub and
flats with 320/400 grit paper or crocus cloth if neces-
sary. Verify that the converter hub o-ring is properly
installed and is free from debris. The hub must be
smooth to avoid damaging the pump seal at installa-
tion.
(1) Lubricate oil pump seal lip with transmission
fluid.
(2) Place torque converter in position on transmis-
sion.
CAUTION: Do not damage oil pump seal or con-
verter hub o-ring while inserting torque converter
into the front of the transmission.
(3) Align torque converter to oil pump seal open-
ing.
(4) Insert torque converter hub into oil pump.
(5) While pushing torque converter inward, rotate
converter until converter is fully seated in the oil
pump gears.
(6) Check converter seating with a scale and
straightedge (Fig. 117). Surface of converter lugs
should be at least 13 mm (1/2 in.) to rear of straight-
edge when converter is fully seated.
(7) If necessary, temporarily secure converter with
C-clamp attached to the converter housing.
Fig. 116 Stator Operation
1 - DIRECTION STATOR WILL FREE WHEEL DUE TO OIL
PUSHING ON BACKSIDE OF VANES
2 - FRONT OF ENGINE
3 - INCREASED ANGLE AS OIL STRIKES VANES
4 - DIRECTION STATOR IS LOCKED UP DUE TO OIL PUSHING
AGAINST STATOR VANES
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 269
TORQUE CONVERTER (Continued)

REMOVAL
(1) Remove the valve body from the transmission
(Fig. 119).
(2) Remove the screws holding the transmission
solenoid/TRS assembly onto the valve body (Fig. 120).
(3) Separate the transmission solenoid/TRS assem-
bly from the valve body.
INSTALLATION
(1) Place TRS selector plate in the PARK position.
(2) Position the transmission solenoid/TRS assem-
bly onto the valve body. Be sure that both alignment
dowels are fully seated in the valve body and that
the TRS switch contacts are properly positioned in
the selector plate
(3) Install the screws to hold the transmission
solenoid/TRS assembly onto the valve body.
(4) Tighten the solenoid assembly screws adjacent
to the arrows cast into the bottom of the valve body
first. Tighten the screws to 5.7 N´m (50 in.lbs.).
(5) Tighten the remainder of the solenoid assembly
screws to 5.7 N´m (50 in.lbs.).
(6) Install the valve body into the transmission.
TRANSMISSION
TEMPERATURE SENSOR
DESCRIPTION
The transmission temperature sensor is a ther-
mistor that is integral to the Transmission Range
Sensor (TRS).
OPERATION
The transmission temperature sensor is used by
the TCM to sense the temperature of the fluid in the
sump. Since fluid temperature can affect transmis-
sion shift quality and convertor lock up, the TCM
requires this information to determine which shift
schedule to operate in.
Calculated Temperature
A failure in the temperature sensor or circuit will
result in calculated temperature being substituted for
actual temperature. Calculated temperature is a pre-
dicted fluid temperature which is calculated from a
combination of inputs:
²Battery (ambient) temperature
²Engine coolant temperature
²In-gear run time since start-up
Fig. 119 Valve Body Bolts
1 - VALVE BODY TO CASE BOLT (6)
Fig. 120 Ttransmission Solenoid/TRS Assembly
Screws
1 - SOLENOID PACK BOLTS (15)
21 - 272 AUTOMATIC TRANSMISSION - 545RFEWJ
TRANSMISSION SOLENOID/TRS ASSEMBLY (Continued)

(2) Remove seal plug from low range fork lockpin
access hole. Then move shift sector to align low range
fork lockpin with access hole.
(3) Remove range fork lockpin with size number
one easy-out tool as follows:
(a) Insert easy-out tool through access hole in
side of transfer case and into lock-pin.
(b) Tap easy-out tool into lock-pin with hammer
until tool is securely engaged into the lock-pin.
(c) Install a t-handle, such as from a tap and die
set, onto the easy-out tool.
(d) Securely tighten the t-handle onto the tool.
(e) In one motion, pull upward and turn the
t-handle counter-clockwise to remove the lock-pin.
(4) Remove shift rail by pulling it straight up and
out of fork (Fig. 27).
(5) Remove mode fork and mainshaft as assembly
(Fig. 28).
(6) Remove mode shift sleeve and mode fork
assembly from mainshaft (Fig. 29). Note position of
mode sleeve in fork and remove sleeve.
Fig. 27 Shift Rail Removal
1 - SHIFT RAIL
2 - MODE FORK
Fig. 28 Mainshaft And Mode Fork Removal
1 - MAINSHAFT ASSEMBLY
2 - MODE FORK
Fig. 29 Separate Mode Fork And Sleeve
1 - MAINSHAFT
2 - MODE SLEEVE
3 - MODE FORK ASSEMBLY
21 - 288 TRANSFER CASE - NV242WJ
TRANSFER CASE - NV242 (Continued)