A conventional mechanical interlock system is also
used. This system manually prohibits shifter move-
ment when the ignition switch is in the LOCK or
ACC positions. Solenoid operation is not required in
these key positions.
For intended BTSI system operation, refer to the
following chart:
ACTION EXPECTED RESPONSE
1. Turn key to the9OFF9
position.1. Shifter CAN be shifted
out of park with brake
pedal applied.
2. Turn key to the
9ON/RUN9position.2. Shifter CANNOT be
shifted out of park.
3. Turn key to the
9ON/RUN9position and
depress the brake pedal.3. Shifter CAN be shifted
out of park.
4. Leave shifter in any
gear and try to return key
to the9LOCK9or9ACC9
position.4. Key cannot be
returned to the9LOCK9or
9ACC9position.
5. Return shifter to
9PARK9and try to remove
the key.5. Key can be removed
(after returning to9LOCK9
position).
6. With the key removed,
try to shift out of9PARK9.6. Shifter cannot be
shifted out of9PARK9.
NOTE: Any failure to meet these expected
responses requires system adjustment or repair.
DIAGNOSIS AND TESTING - BRAKE/
TRANSMISSION SHIFT INTERLOCK SOLENOID
For intended BTSI system operation, refer to the
following chart:
ACTION EXPECTED RESPONSE
1. Turn key to the9OFF9
position.1. Shifter CAN be shifted
out of park with brake
pedal applied.
2. Turn key to the
9ON/RUN9position.2. Shifter CANNOT be
shifted out of park.
3. Turn key to the
9ON/RUN9position and
depress the brake pedal.3. Shifter CAN be shifted
out of park.
4. Leave shifter in any
gear and try to return key
to the9LOCK9or9ACC9
position.4. Key cannot be
returned to the9LOCK9or
9ACC9position.
5. Return shifter to
9PARK9and try to remove
the key.5. Key can be removed
(after returning to9LOCK9
position).
ACTION EXPECTED RESPONSE
6. With the key removed,
try to shift out of9PARK9.6. Shifter cannot be
shifted out of9PARK9.
NOTE: Any failure to meet these expected
responses requires system repair. Refer to the
appropriate Diagnostic Information.
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove instrument panel lower shroud (Fig.
296).
(3) Remove knee bolster (Fig. 297).
Fig. 296 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 297 Knee Bolster
1 - KNEE BOLSTER
21 - 266 41TE AUTOMATIC TRANSAXLERS
SHIFT INTERLOCK SOLENOID (Continued)
(3) Install steering column lower shroud.
(4) Install knee bolster (Fig. 302).
(5) Install instrument panel lower silencer (Fig.
303).
(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. 304)
is external to the transaxle and mounted to thetransaxle 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.
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
Fig. 302 Knee Bolster
1 - KNEE BOLSTER
Fig. 303 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 304 Solenoid/Pressure Switch Assembly
1 - SOLENOID AND PRESSURE SWITCH ASSEMBLY
21 - 268 41TE AUTOMATIC TRANSAXLERS
SHIFT INTERLOCK SOLENOID (Continued)
OPERATION
The Transmission Range Sensor (TRS) (Fig. 331)
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. 332)
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. 333).
(3) Remove TRS from manual shaft.
INSTALLATION
(1) Install transmission range sensor (TRS) to the
valve body and torque retaining screw (Fig. 333) to 5
N´m (45 in. lbs.).
(2) Install valve body to transaxle. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
41TE/VALVE BODY - INSTALLATION)
Fig. 333 Remove Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL VALVE CONTROL PIN
3 - RETAINING SCREW
21 - 282 41TE AUTOMATIC TRANSAXLERS
TRANSMISSION RANGE SENSOR (Continued)
VALVE BODY
DESCRIPTION
The valve body assembly consists of a cast alumi-
num valve body, a separator plate, and transfer
plate. The valve body contains valves and check balls
that control fluid delivery to the torque converter
clutch, solenoid/pressure switch assembly, and fric-
tional clutches. The valve body contains the following
components (Fig. 334):
²Regulator valve
²Solenoid switch valve
²Manual valve
²Converter clutch switch valve
²Converter clutch control valve
²Torque converter regulator valve
²Low/Reverse switch valve
In addition, the valve body also contains the ther-
mal valve, #2,3&4 check balls, the #5 (overdrive)
check valve and the 2/4 accumulator assembly. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 41TE/VALVE BODY - DISASSEMBLY)
OPERATION
NOTE: Refer to the Hydraulic Schematics for a
visual aid in determining valve location, operation
and design.
REGULATOR VALVE
The regulator valve controls hydraulic pressure in
the transaxle. It receives unregulated pressure from
the pump, which works against spring tension to
maintain oil at specific pressures. A system of sleeves
and ports allows the regulator valve to work at one of
three predetermined pressure levels. Regulated oil
pressure is also referred to as ªline pressure.º
SOLENOID SWITCH VALVE
The solenoid switch valve controls line pressure
from the LR/CC solenoid. In one position, it allows
the low/reverse clutch to be pressurized. In the other,
it directs line pressure to the converter control and
converter clutch valves.
Fig. 334 Valve Body Assembly
1 - VALVE BODY 5 - MANUAL VALVE
2 - T/C REGULATOR VALVE 6 - CONVERTER CLUTCH SWITCH VALVE
3 - L/R SWITCH VALVE 7 - SOLENOID SWITCH VALVE
4 - CONVERTER CLUTCH CONTROL VALVE 8 - REGULATOR VALVE
RS41TE AUTOMATIC TRANSAXLE21 - 283
MANUAL VALVE
The manual valve is operated by the mechanical
shift linkage. Its primary responsibility is to send
line pressure to the appropriate hydraulic circuits
and solenoids. The valve has three operating ranges
or positions.
CONVERTER CLUTCH SWITCH VALVE
The main responsibility of the converter clutch
switch valve is to control hydraulic pressure applied
to the front (off) side of the converter clutch piston.
Line pressure from the regulator valve is fed to the
torque converter regulator valve, where it passes
through the valve, and is slightly regulated. The
pressure is then directed to the converter clutch
switch valve and to the front side of the converter
clutch piston. This pressure pushes the piston back
and disengages the converter clutch.
CONVERTER CLUTCH CONTROL VALVE
The converter clutch control valve controls the
back (on) side of the torque converter clutch. When
the PCM/TCM energizes or modulates the LR/CC
solenoid to apply the converter clutch piston, both
the converter clutch control valve and the converter
control valve move, allowing pressure to be applied to
the back side of the clutch.
T/C REGULATOR VALVE
The torque converter regulator valve slightly regu-
lates the flow of fluid to the torque converter.
LOW/REVERSE SWITCH VALVE
The low/reverse clutch is applied from different
sources, depending on whether low (1st) gear or
reverse is selected. The low/reverse switch valve
alternates positions depending on from which direc-
tion fluid pressure is applied. By design, when the
valve is shifted by fluid pressure from one channel,
the opposing channel is blocked. The switch valve
alienates the possibility of a sticking ball check, thus
providing consistent application of the low/reverse
clutch under all operating conditions.
REMOVAL
NOTE: If valve body is replaced or reconditioned,
the ªQuick-Learnº Procedure must be performed.
(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROLMODULES/TRANSMISSION CONTROL MODULE -
STANDARD PROCEDURE)
(1) Disconnect battery negative cable.
(2) Disconnect gearshift cable from manual valve
lever.
(3) Remove manual valve lever from manual shaft.
(4) Raise vehicle on hoist.
(5) Remove oil pan bolts (Fig. 335).
(6) Remove oil pan (Fig. 336).
Fig. 335 Oil Pan Bolts
1 - OIL PAN BOLTS (USE RTV UNDER BOLT HEADS)
Fig. 336 Oil Pan
1 - OIL PAN
2 - 1/8 INCH BEAD OF RTV SEALANT
3 - OIL FILTER
21 - 284 41TE AUTOMATIC TRANSAXLERS
VALVE BODY (Continued)
DISASSEMBLY
NOTE: If valve body assembly is being recondi-
tioned, the PCM/TCM Quick Learn Procedure must
be performed. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/TRANSMISSION
CONTROL MODULE - STANDARD PROCEDURE)
(1) Remove manual shaft seal (Fig. 341).
(2) Remove Transmission Range Sensor retaining
screw (Fig. 342).(3) Remove Manual Shaft/Rooster Comb and
Transmission Range Sensor (Fig. 343).
(4) Remove 2/4 Accumulator Retaining Plate (Fig.
344).
Fig. 341 Manual Shaft Seal
1 - SEAL
2 - MANUAL SHAFT
Fig. 342 Remove Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL VALVE CONTROL PIN
3 - RETAINING SCREW
Fig. 343 Manual Shaft/Rooster Comb and
Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL SHAFT
3 - ROOSTER COMB
Fig. 344 2/4 Accumulator Retaining Plate
1 - 2±4 ACCUMULATOR RETAINING PLATE
2 - DETENT SPRING
21 - 286 41TE AUTOMATIC TRANSAXLERS
VALVE BODY (Continued)
(11) Install twenty-four transfer plate to valve
body screws (Fig. 366) and torque to 5 N´m (45 in.
lbs.).
(12) Install 2/4 Accumulator components as shown
in (Fig. 367).(13) Torque 2/4 Accumulator retainer to 5 N´m (45
in. lbs.) (Fig. 368).
(14) Install Manual Shaft/Rooster Comb and
Transmission Range Sensor (Fig. 369).
Fig. 366 Install Valve Body to Transfer Plate Screws
1 - SCREW (24)
2 - TRANSFER PLATE
3 - VALVE BODY
Fig. 367 2/4 Accumulator Assembly
1 - VALVE BODY
2 - RETAINER PLATE
3 - DETENT SPRING
4 - RETURN SPRINGS
5 - PISTON
Fig. 368 2/4 Accumulator Retaining Plate
1 - 2±4 ACCUMULATOR RETAINING PLATE
2 - DETENT SPRING
Fig. 369 Install Manual Shaft/Rooster Comb and
Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL SHAFT
3 - ROOSTER COMB
21 - 294 41TE AUTOMATIC TRANSAXLERS
VALVE BODY (Continued)
(15) Make sure Manual Valve control pin is con-
tained within the rooster comb slot (Fig. 370). Install
Transmission Range Sensor retaining screw (Fig.
370) and torque to 5 N´m (45 in. lbs.).
(16) Install manual shaft seal (Fig. 371).INSTALLATION
NOTE: If valve body assembly is being replaced or
reconditioned, the ªQuick-Learnº procedure must
be performed. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/TRANSMISSION
CONTROL MODULE - STANDARD PROCEDURE)
(1) Install valve body assembly to transaxle (Fig.
372). Install and torque valve body-to-transaxle case
bolts (Fig. 373) to 12 N´m (105 in. lbs.).
Fig. 370 Install Transmission Range Sensor
Retaining Screw
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL VALVE CONTROL PIN
3 - RETAINING SCREW
Fig. 371 Manual Shaft Seal
1 - SEAL
2 - MANUAL SHAFT
Fig. 372 Valve Body Removal/Installation
1 - VALVE BODY
Fig. 373 Valve Body Attaching Bolts
1 - VALVE BODY ATTACHING BOLTS (18)
2 - VALVE BODY
RS41TE AUTOMATIC TRANSAXLE21 - 295
VALVE BODY (Continued)