Page 1619 of 2177
Reverse Block (Shift to Reverse W/Speed Over 8 mph)
21 - 172 41TE AUTOMATIC TRANSAXLERS
41TE AUTOMATIC TRANSAXLE (Continued)
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Page 1636 of 2177

OPERATION
The function of an accumulator is to cushion the
application of a frictional clutch element. When pres-
surized fluid is applied to a clutch circuit, the appli-
cation force is dampened by fluid collecting in the
respective accumulator chamber against the piston
and spring(s). The intended result is a smooth, firm
clutch application.
AUTOSTICK SWITCH
DESCRIPTION
Autostick is a driver-interactive transaxle feature
that offers manual gear shifting capability. The control
switch is part of the transaxle gear shift lever as
shown in (Fig. 171). It can only be serviced by replac-
ing the gearshift lever assembly. (Refer to 19 - STEER-
ING/COLUMN/GEAR SHIFT LEVER - REMOVAL)
OPERATION
When the shift lever is moved into the Autostick
position (as indicated by the Shift Lever Position
Indicator in the cluster), the transaxle remains in
whatever gear it was using before Autostick was acti-
vated. The TCM sends a 5 volt signal through the
switch and then monitors the signal for voltage drop.
Each switch state (driver command) results in a spe-
cific voltage reading sensed by the TCM. The TCM
then determines transaxle operation (upshift/down-
shift/OD Lockout) based on their corresponding volt-
age. Refer to the following chart for corresponding
switch states and voltage readings:
Switch State Voltage Reading
Autostick DOWN
depressed0.3V-1.6V
Autostick UP depressed 1.6V-2.8V
Overdrive OFF9Lockout9
depressed2.8V-3.8V
All switches open 3.8V-4.8V
-Voltage values <.3V and >4.8V are considered
INVALID and will result in a DTC
Fig. 169 Low/Reverse Accumulator Assembly
1 - ACCUMULATOR PISTON
2 - SEAL RINGS
3 - RETURN SPRINGS
4 - (NOTE NOTCH)
Fig. 170 2/4 Accumulator Assembly
1 - VALVE BODY
2 - RETAINER PLATE
3 - DETENT SPRING
4 - SPRINGS
5 - SEALS
6 - PISTON
Fig. 171 Autostick Switch Location (if equipped)
RS41TE AUTOMATIC TRANSAXLE21 - 189
ACCUMULATOR (Continued)
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Page 1679 of 2177

ASSEMBLY
(1) Assemble oil pump as shown in (Fig. 287)
(2) Install and torque reaction shaft support-to-oil
pump housing bolts to 28 N´m (20 ft. lbs.) torque.
PLANETARY GEARTRAIN
DESCRIPTION
The planetary geartrain is located between the
input clutch assembly and the rear of the transaxle
case. The planetary geartrain consists of two sun
gears, two planetary carriers, two annulus (ring)
gears, and one output shaft (Fig. 288).
OPERATION
The planetary geartrain utilizes two planetary gear
sets that connect the transmission input shaft to the
output shaft. Input and holding clutches drive or lock
different planetary members to change output ratio
or direction.
SEAL - OIL PUMP
REMOVAL
(1) Remove transaxle from vehicle (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - 41TE
- REMOVAL).
(2) Using Tool C-3981-B, remove oil pump seal
(Fig. 289).
Fig. 287 Oil Pump Assembly
1 - PUMP HOUSING
2 - OUTER PUMP GEAR
3 - INNER PUMP GEAR
4 - REACTION SHAFT SUPPORT
5 - SEAL RINGS (4)
6 - REACTION SHAFT
7 - CRESCENT
Fig. 288 Planetary Geartrain
1 - FRONT SUN GEAR ASSEMBLY
2 - #6 THRUST BEARING
3 - #7 THRUST BEARING
4 - REAR CARRIER/FRONT ANNULUS ASSEMBLY
5 - REAR SUN GEAR
6 - FRONT CARRIER/REAR ANNULUS ASSEMBLY
Fig. 289 Remove Oil Pump Seal
1 - TOOL C-3981±B
2 - OIL PUMP SEAL
21 - 232 41TE AUTOMATIC TRANSAXLERS
OIL PUMP (Continued)
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Page 1680 of 2177

INSTALLATION
(1) Using Tool C-4193, install oil pump seal (Fig.
290).
(2) Install transaxle to vehicle (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - 41TE
- INSTALLATION).
SHIFT INTERLOCK SOLENOID
DESCRIPTION
The Brake/Transmission Shift Interlock system
consists of an electro-magnetic solenoid mounted to
the steering column (Fig. 291). The solenoid's plunger
consists of an integrated hook, which operates the
shift lever pawl (part of shift lever assembly), and a
plunger return spring (Fig. 292). The solenoid also
has an integrated bracket, which facilitates fastening
to the steering column.
OPERATION
The Brake/Transmission Shift Interlock (BTSI) Sole-
noid prevents the transmission shift lever from being
moved out of PARK (P) unless the brake pedal is
applied. The BTSI solenoid is hardwired to and con-
trolled by the Intelligent Power Module (IPM). Battery
voltage is applied to one side of the solenoid with the
ignition key is in either the OFF, ON/RUN, or START
positions (Fig. 293). The ground side of the solenoid is
controlled by a driver within the IPM. It relies on volt-
age supplied from the stop lamp switch to the stop
lamp sense circuit within the IPM to tell when the
brake pedal is depressed. When the brake pedal is
depressed, the ground circuit opens, de-energizing the
solenoid. When the brake pedal is released, the ground
circuit is closed, energizing the solenoid.
When the ignition key is in either the OFF,
ON/RUN, or START positions, the BTSI solenoid is
energized, and the solenoid plunger hook pulls the
shift lever pawl into position, prohibiting the shift
lever from moving out of PARK (P) (Fig. 294). When
the brake pedal is depressed, the ground circuit
opens, de-energizing the solenoid. This moves the
gearshift lever pawl out of the way (Fig. 295), allow-
ing the shift lever to be moved into any gear position.
Fig. 290 Install Oil Pump Seal
1 - TOOL C-4193
2 - HANDLE TOOL C-4171
Fig. 291 Brake/Transmission Shift Interlock (BTSI)
Solenoid Location
1 - BTSI SOLENOID
Fig. 292 Solenoid Plunger and Return Spring
1 - PLUNGER
2 - RETURN SPRING
3 - BTSI SOLENOID
RS41TE AUTOMATIC TRANSAXLE21 - 233
SEAL - OIL PUMP (Continued)
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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.
Fig. 293 Ignition Key/Switch Positions
1 - ACC
2 - LOCK
3 - OFF
4 - ON/RUN
5-START
Fig. 294 Pawl Engaged to Shift Lever
1 - GEAR SHIFT LEVER
2 - GEAR SHIFT LEVER PAWL
Fig. 295 Pawl Disengaged From Shift Lever
1 - GEAR SHIFT LEVER
2 - GEAR SHIFT LEVER PAWL
21 - 234 41TE AUTOMATIC TRANSAXLERS
SHIFT INTERLOCK SOLENOID (Continued)
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Page 1682 of 2177

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).
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).
(4) Remove steering column lower shroud.
(5) Disconnect brake/transmission shift interlock
(BTSI) solenoid connector (Fig. 298).
(6) Remove two (2) solenoid-to-column screws (Fig.
299).
(7) Remove solenoid.
Fig. 296 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 297 Knee Bolster
1 - KNEE BOLSTER
Fig. 298 BTSI Solenoid Connector
1 - BTSI SOLENOID
2 - SOLENOID CONNECTOR
RS41TE AUTOMATIC TRANSAXLE21 - 235
SHIFT INTERLOCK SOLENOID (Continued)
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Page 1683 of 2177
INSTALLATION
(1) Place interlock solenoid into position ensuring
hook on end of solenoid plunger engages gearshift
lever pawl pin. Install and tighten screws (Fig. 300).(2) Verify gearshift lever is in PARK (P) and con-
nect solenoid connector (Fig. 301).
(3) Install steering column lower shroud.
(4) Install knee bolster (Fig. 302).
Fig. 299 Solenoid Retaining Screw
1 - SOLENOID RETAINING SCREW (2)
Fig. 300 Solenoid Retaining Screw
1 - SOLENOID RETAINING SCREW (2)
Fig. 301 BTSI Solenoid Connector
1 - BTSI SOLENOID
2 - SOLENOID CONNECTOR
Fig. 302 Knee Bolster
1 - KNEE BOLSTER
21 - 236 41TE AUTOMATIC TRANSAXLERS
SHIFT INTERLOCK SOLENOID (Continued)
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Page 1684 of 2177

(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 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.
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.
Fig. 303 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 304 Solenoid/Pressure Switch Assembly
1 - SOLENOID AND PRESSURE SWITCH ASSEMBLY
RS41TE AUTOMATIC TRANSAXLE21 - 237
SHIFT INTERLOCK SOLENOID (Continued)
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