(27) Lower engine/transaxle assembly with screw
jack.
(28) Obtain helper and/or transmission jack.
Secure transmission jack to transaxle assembly.
(29) Remove upper mount bracket from transaxle
(Fig. 14).
(30) Remove remaining transaxle bellhousing-to-
engine bolts.
(31) Remove transaxle assembly from vehicle.
DISASSEMBLY
NOTE: If transaxle is being overhauled (clutch
and/or seal replacement) or replaced, it is neces-
sary to perform the PCM/TCM Quick Learn Proce-
dure. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN/TRANSMIS-
SION CONTROL MODULE - STANDARD PROCE-
DURE)
NOTE: This procedure does not include final drive
(differential) disassembly.
(1) Remove input and output speed sensors.
(2) Remove three (3) solenoid/pressure switch
assembly-to-case bolts.
(3) Remove solenoid/pressure switch assembly and
gasket (Fig. 15).(4) Remove oil pan-to-case bolts (Fig. 16).
(5) Remove oil pan (Fig. 17).
Fig. 15 Solenoid/Pressure Switch Assembly and
Gasket
1 - SOLENOID/PRESSURE SWITCH ASSEMBLY
2 - GASKET
Fig. 16 Remove Oil Pan Bolts
1 - OIL PAN BOLTS (USE RTV UNDER BOLT HEADS)
Fig. 17 Remove Oil Pan
1 - OIL PAN
2 - 1/8 INCH BEAD OF MOPARTATF RTV (MS-GF41)
3 - OIL FILTER
21 - 12 40TE AUTOMATIC TRANSAXLERS
40TE AUTOMATIC TRANSAXLE (Continued)
(66) Using a hammer and suitable drift, drive out
inner output bearing cup (Fig. 83).
(67) Using tool 6062, remove outer output bearing
cup (Fig. 84).
ASSEMBLY
CAUTION: The cooler bypass valve must be
replaced if transaxle failure has occurred. Do not
attempt to reuse or clean old valve.NOTE: If transaxle is being overhauled (clutch
and/or seal replacement), the TCM/PCM Quick Learn
procedure must be performed. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/TRANS-
MISSION CONTROL MODULE - STANDARD
PROCEDURE)
(1) Install both output bearing cups using Tool
5050 (Fig. 85).
(2) Install low/reverse piston retainer gasket (Fig.
86). Make sure gasket holes line up with case.
Fig. 83 Remove Output Bearing Inner Cup
1 - OUTPUT BEARING CUPS (REPLACE IN PAIRS)
2 - HAMMER
3 - BRASS DRIFT
Fig. 84 Remove Output Bearing Outer
1 - TOOL 6062
Fig. 85 Install Both Output Bearing Cups
1 - OUTPUT BEARING CUPS
2 - WRENCHES
3 - TOOL 5050
Fig. 86 Install Piston Retainer Gasket
1 - GASKET HOLES MUST LINE UP
2 - LOW/REVERSE CLUTCH PISTON RETAINER GASKET
RS40TE AUTOMATIC TRANSAXLE21-29
40TE AUTOMATIC TRANSAXLE (Continued)
(3) Install steering column lower shroud.
(4) Install knee bolster (Fig. 278).
(5) Install instrument panel lower silencer (Fig.
279).
(6) Connect battery negative cable.
(7) Verify proper shift interlock system operation.
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 31TH/SHIFT INTERLOCK SOLENOID -
OPERATION)SOLENOID/PRESSURE
SWITCH ASSY
DESCRIPTION
The Solenoid/Pressure Switch Assembly (Fig. 280)
is external to the transaxle and mounted to the
transaxle case. The assembly consists of four sole-
noids that control hydraulic pressure to the LR/CC,
2/4, OD, and UD friction elements. The reverse
clutch is controlled by line pressure from the manual
valve in the valve body. The solenoids are contained
within the Solenoid/Pressure Switch Assembly, and
can only be serviced by replacing the assembly.
The solenoid assembly also contains pressure
switches that monitor and send hydraulic circuit
information to the PCM/TCM. Likewise, the pressure
switches can only be service by replacing the assem-
bly.
Fig. 278 Knee Bolster
1 - KNEE BOLSTER
Fig. 279 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCERFig. 280 Solenoid/Pressure Switch Assembly
1 - SOLENOID AND PRESSURE SWITCH ASSEMBLY
RS40TE AUTOMATIC TRANSAXLE21 - 117
SHIFT INTERLOCK SOLENOID (Continued)
OPERATION
SOLENOIDS
The solenoids receive electrical power from the
Transmission Control Relay through a single wire.
The PCM/TCM energizes or operates the solenoids
individually by grounding the return wire of the sole-
noid needed. When a solenoid is energized, the sole-
noid valve shifts, and a fluid passage is opened or
closed (vented or applied), depending on its default
operating state. The result is an apply or release of a
frictional element.
The 2/4 and UD solenoids are normally applied,
which by design allow fluid to pass through in their
relaxed or ªoffº state. This allows transaxle limp-in
(P,R,N,2) in the event of an electrical failure.
The continuity of the solenoids and circuits are
periodically tested. Each solenoid is turned on or off
depending on its current state. An inductive spike
should be detected by the PCM/TCM during this test.
It no spike is detected, the circuit is tested again to
verify the failure. In addition to the periodic testing,
the solenoid circuits are tested if a speed ratio or
pressure switch error occurs.
PRESSURE SWITCHES
The PCM/TCM relies on three pressure switches to
monitor fluid pressure in the L/R, 2/4, and OD
hydraulic circuits. The primary purpose of these
switches is to help the PCM/TCM detect when clutch
circuit hydraulic failures occur. The range for the
pressure switch closing and opening points is 11-23
psi. Typically the switch opening point will be
approximately one psi lower than the closing point.
For example, a switch may close at 18 psi and open
at 17 psi. The switches are continuously monitored
by the PCM/TCM for the correct states (open or
closed) in each gear as shown in the following chart:
PRESSURE SWITCH STATES
GEAR L/R 2/4 OD
ROPOPOP
P/N CL OP OP
1st CL OP OP
2nd OP CL OP
DOPOPCL
OD OP CL CL
OP = OPEN
CL = CLOSED
A Diagnostic Trouble Code (DTC) will set if the
PCM/TCM senses any switch open or closed at the
wrong time in a given gear.The PCM/TCM also tests the 2/4 and OD pressure
switches when they are normally off (OD and 2/4 are
tested in 1st gear, OD in 2nd gear, and 2/4 in 3rd
gear). The test simply verifies that they are opera-
tional, by looking for a closed state when the corre-
sponding element is applied. Immediately after a
shift into 1st, 2nd, or 3rd gear with the engine speed
above 1000 rpm, the PCM/TCM momentarily turns
on element pressure to the 2/4 and/or OD clutch cir-
cuits to identify that the appropriate switch has
closed. If it doesn't close, it is tested again. If the
switch fails to close the second time, the appropriate
Diagnostic Trouble Code (DTC) will set.
REMOVAL
NOTE: If solenoid/pressure switch assembly is
being replaced, the ªQuick-Learnº procedure must
be performed. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/TRANSMISSION
CONTROL MODULE - STANDARD PROCEDURE)
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly.
(3) Disconnect solenoid/pressure switch assembly
connector (Fig. 281).
(4) Disconnect input speed sensor connector (Fig.
281).
Fig. 281 Transmission Connectors
1 - SOLENOID PACK CONNECTOR
2 - INPUT SPEED SENSOR CONNECTOR
3 - OUTPUT SPEED SENSOR CONNECTOR
4 - TRANSMISSION RANGE SENSOR CONNECTOR
21 - 118 40TE AUTOMATIC TRANSAXLERS
SOLENOID/PRESSURE SWITCH ASSY (Continued)
SPEED SENSOR - INPUT
DESCRIPTION
The Input Speed Sensor is a two-wire magnetic
pickup device that generates AC signals as rotation
occurs. It is threaded into the transaxle case (Fig.
285), sealed with an o-ring (Fig. 286), and is consid-
ered a primary input to the Powertrain/Transmission
Control Module.
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 (Fig.
287), an AC voltage is generated and sent to the
PCM/TCM. The PCM/TCM interprets this informa-
tion as input shaft rpm.
The PCM/TCM compares the input speed signal
with output speed signal to determine the following:
²Transmission gear ratio
²Speed ratio error detection
²CVI calculation
The PCM/TCM also compares the input speed sig-
nal and the engine speed signal to determine the fol-
lowing:
²Torque converter clutch slippage
²Torque converter element speed ratio
Fig. 285 Input Speed Sensor Location
1 - INPUT SPEED SENSOR
Fig. 286 O-Ring Location
1 - INPUT SPEED SENSOR
2 - O-RING
Fig. 287 Sensor Relation to Input Clutch Hub
1 - INPUT SPEED SENSOR
2 - TRANSAXLE CASE
3 - INPUT CLUTCH HUB
21 - 120 40TE AUTOMATIC TRANSAXLERS
SPEED SENSOR - OUTPUT
DESCRIPTION
The Output Speed Sensor is a two-wire magnetic
pickup device that generates an AC signal as rotation
occurs. It is threaded into the transaxle case (Fig.
291), sealed with an o-ring (Fig. 292), and is consid-
ered a primary input to the Powetrain/Transmission
Control Module.
OPERATION
The Output Speed Sensor provides information on
how fast the output shaft is rotating. As the rear
planetary carrier park pawl lugs pass by the sensor
coil (Fig. 293), an AC voltage is generated and sent to
the PCM/TCM. The PCM/TCM interprets this infor-
mation as output shaft rpm.
The PCM/TCM compares the input and output
speed signals to determine the following:
²Transmission gear ratio
²Speed ratio error detection
²CVI calculation
Fig. 291 Output Speed Sensor
1 - OUTPUT SPEED SENSOR
Fig. 292 O-Ring Location
1 - OUTPUT SPEED SENSOR
2 - O-RING
Fig. 293 Sensor Relation to Planet Carrier Park Pawl
1 - OUTPUT SPEED SENSOR
2 - REAR PLANET CARRIER/OUTPUT SHAFT ASSEMBLY
3 - TRANSAXLE CASE
21 - 122 40TE AUTOMATIC TRANSAXLERS
TRANSMISSION CONTROL
RELAY
DESCRIPTION
The transmission control relay (Fig. 306) is located
in the Intelligent Power Module (IPM), which is
located on the left side of the engine compartment
between the battery and left fender.
OPERATION
The relay is supplied fused B+ voltage, energized by
the PCM/TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal operating
mode. When the relay is ªoffº, no power is supplied to
the solenoid pack and the transmission is in ªlimp-inº
mode. After a controller reset (ignition key turned to the
ªrunº position or after cranking engine), the PCM/TCM
energizes the relay. Prior to this, the PCM/TCM verifies
that the contacts are open by checking for no voltage at
the switched battery terminals. After this is verified,
the voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the PCM/TCM
monitors the terminals to verify that the voltage is
greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is mounted
to the top of the valve body inside the transaxle andcan only be serviced by removing the valve body. The
electrical connector extends through the transaxle
case (Fig. 307).
The Transmission Range Sensor (TRS) has four
switch contacts that monitor shift lever position and
send the information to the PCM/TCM.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transaxle tem-
perature to the TCM and PCM (Fig. 308).
Fig. 306 Transmission Control Relay Location
1 - TRANSMISSION CONTROL RELAY
2 - LEFT FENDER
3 - INTELLIGENT POWER MODULE (IPM)
4 - BATTERY
Fig. 307 Transmission Range Sensor (TRS)
Location
1 - TRANSMISSION RANGE SENSOR
Fig. 308 Transmission Temperature Sensor
1 - TRANSMISSION RANGE SENSOR
2 - TEMPERATURE SENSOR
21 - 130 40TE AUTOMATIC TRANSAXLERS
OPERATION
The Transmission Range Sensor (TRS) (Fig. 307)
communicates shift lever position (SLP) to the PCM/
TCM as a combination of open and closed switches.
Each shift lever position has an assigned combina-
tion of switch states (open/closed) that the PCM/TCM
receives from four sense circuits. The PCM/TCM
interprets this information and determines the
appropriate transaxle gear position and shift sched-
ule.
Since there are four switches, there are 16 possible
combinations of open and closed switches (codes).
Seven of these codes are related to gear position and
three are recognized as ªbetween gearº codes. This
results in six codes which should never occur. These
are called ªinvalidº codes. An invalid code will result
in a DTC, and the PCM/TCM will then determine the
shift lever position based on pressure switch data.
This allows reasonably normal transmission opera-
tion with a TRS failure.
TRS SWITCH STATES
SLP T42 T41 T3 T1
PCL CL CL OP
RCL OP OP OP
NCL CL OP CL
ODOP OP OP CL
3OP OP CL OP
LCL OP CL CL
TRANSMISSION TEMPERATURE SENSOR
The TRS has an integrated thermistor (Fig. 308)
that the PCM/TCM uses to monitor the transmis-
sion's sump temperature. Since fluid temperature
can affect transmission shift quality and convertor
lock up, the PCM/TCM requires this information to
determine which shift schedule to operate in. The
PCM also monitors this temperature data so it can
energize the vehicle cooling fan(s) when a transmis-
sion ªoverheatº condition exists. If the thermistor cir-
cuit fails, the PCM/TCM will revert to calculated oil
temperature usage.
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
REMOVAL
(1) Remove valve body assembly from transaxle.
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 41TE/VALVE BODY - REMOVAL)
(2) Remove transmission range sensor retaining
screw and remove sensor from valve body (Fig. 309).
(3) Remove TRS from manual shaft.
INSTALLATION
(1) Install transmission range sensor (TRS) to the
valve body and torque retaining screw (Fig. 309) to 5
N´m (45 in. lbs.).
(2) Install valve body to transaxle. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
41TE/VALVE BODY - INSTALLATION)
Fig. 309 Remove Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL VALVE CONTROL PIN
3 - RETAINING SCREW
RS40TE AUTOMATIC TRANSAXLE21 - 131
TRANSMISSION RANGE SENSOR (Continued)