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(5) Reinstall gears to pump body and measure
outer gear-to-pocket clearance with a feeler gauge
(Fig. 184).Outer gear-to-pocket clearance should
be within 0.045-0.141 mm (0.0018-0.0056 in.).
(6) Measure both inner and outer gear side clear-
ance with PlastigageŸ. If PlastigageŸ is not avail-
able, measure across the pump body with a straight
edge and feeler gauge.
(a) Position an appropriate piece of PlastigageŸ
across both gears.
(b) Align the plastigage to a flat area on the
reaction shaft housing.
(c) Install the reaction shaft support to the
pump housing and torque to 28 N´m (250 in. lbs.).
(d) Separate the reaction shaft housing from the
pump housing and measure the PlastigageŸ fol-
lowing the instructions supplied with it.Inner
and outer gear side clearance should be
within 0.020-0.046 mm (0.0008-0.0018 in.).
ASSEMBLY
(1) Install inner and outer gears to pump body
(Fig. 183). Lubricate gears with MopartATF+4
(Automatic Transmission Fluid-Type 9602).
(2) Install reaction shaft support to pump body
and align holes.
(3) Install and torque reaction shaft support-to-
pump body bolts to 28 N´m (250 in. lbs.).
PARK/NEUTRAL POSITION
SWITCH
DIAGNOSIS AND TESTING - PARK/NEUTRAL
POSITION SWITCH
The park/neutral starting switch is the center ter-
minal of the 3 terminal switch. It provides ground for
the starter solenoid circuit through the selector lever
in only Park (P) and Neutral (N) positions.
(1) To test switch, remove wiring connector from
switch and test for continuity between center pin of
switch and transaxle case. Continuity should exist
only when transaxle is in Park or Neutral.
(2) Check gearshift cable adjustment before replac-
ing a switch which tests bad.
REMOVAL
(1) Unscrew switch from transaxle case allowing
fluid to drain into a container. Move selector lever to
Park, then to Neutral position, and inspect to see the
switch operating lever fingers are centered in switch
opening.
INSTALLATION
(1) Screw the switch with a new seal into trans-
axle case and tighten to 33 N´m (24 ft. lbs.). Retest
switch with the test lamp.
(2) Add fluid to transaxle to bring up to proper
level.
(3) The back-up lamp switch circuit is through the
two outside terminals of the 3 terminal switch.
(4) To test switch, remove wiring connector from
switch and test for continuity between the two out-
side pins.
(5) Continuity should exist only with transaxle in
Reverse position.
(6) No continuity should exist from either pin to
the case.Fig. 184 Measuring Pump Outer Gear-to-Pocket
Clearance
1 - FEELER GAUGE
2 - OUTER GEAR
RS31TH AUTOMATIC TRANSAXLE21 - 107
OIL PUMP (Continued)
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ASSEMBLY
(1) Install low/reverse servo assembly (Fig. 208).
(2) Install low/reverse servo snap ring (Fig. 205).
SHIFT INTERLOCK SOLENOID
DESCRIPTION
The Brake/Transmission Shift Interlock system
consists of an electro-magnetic solenoid mounted to
the steering column (Fig. 209). 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. 210). The solenoid also
has an integrated bracket, which facilitates fastening
to the steering column.
OPERATION
The Brake/Transmission Shift Interlock (BTSI)
Solenoid 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
controlled 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. 211). The ground side of the
solenoid is controlled by a driver within the IPM. It
relies on voltage 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-ener-
gizing the solenoid. When the brake pedal is
released, the ground circuit is closed, energizing the
solenoid.
Fig. 208 Low/Reverse Servo Assembly
1 - SERVO PISTON
2 - SPRINGFig. 209 Brake/Transmission Shift Interlock (BTSI)
Solenoid Location
1 - BTSI SOLENOID
Fig. 210 Solenoid Plunger and Return Spring
1 - PLUNGER
2 - RETURN SPRING
3 - BTSI SOLENOID
RS31TH AUTOMATIC TRANSAXLE21 - 115
SERVO - LOW/REVERSE (Continued)
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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.
214).(3) Remove knee bolster (Fig. 215).
(4) Remove steering column lower shroud.
(5) Disconnect brake/transmission shift interlock
(BTSI) solenoid connector (Fig. 216).
Fig. 214 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 215 Knee Bolster
1 - KNEE BOLSTER
Fig. 216 BTSI Solenoid Connector
1 - BTSI SOLENOID
2 - SOLENOID CONNECTOR
RS31TH AUTOMATIC TRANSAXLE21 - 117
SHIFT INTERLOCK SOLENOID (Continued)
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(5) Install instrument panel lower silencer (Fig.
221).
(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 - TCC
DESCRIPTION
The torque converter clutch (TCC) solenoid is fas-
tened to the transaxle valve body, and its connector
protrudes through the transaxle case (Fig. 222).
OPERATION
The torque converter clutch solenoid is responsible
for controlling application of the torque converter
clutch. It is controlled by the Powertrain Control
Module (PCM), which determines when conditions
are acceptable for torque converter lock-up.
REMOVAL
(1) Remove valve body from transaxle. (Refer to 21
- TRANSMISSION/TRANSAXLE/AUTOMATIC -
31TH/VALVE BODY - REMOVAL)
(2) Remove three (3) torque converter clutch sole-
noid-to-valve body screws (Fig. 223).
(3) Remove torque converter clutch solenoid (Fig.
223). Note orientation of plug and spring.
Fig. 221 Instrument Panel Lower Silencer
1 - INSTRUMENT PANEL LOWER SILENCER
Fig. 222 Torque Converter Clutch Solenoid
1 - TCC SOLENOID WIRING CONNECTOR
RS31TH AUTOMATIC TRANSAXLE21 - 119
SHIFT INTERLOCK SOLENOID (Continued)
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INSTALLATION
(1) Install plug and spring as shown in (Fig. 223).
(2) Install torque converter clutch solenoid to valve
body (Fig. 223) and torque screws to 5 N´m (45 in.
lbs.).
(3) Install valve body to transaxle. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
31TH/VALVE BODY - INSTALLATION)
THROTTLE VALVE CABLE
REMOVAL
(1) Disconnect battery negative cable.
(2) Disconnect cable core from throttle lever pin
(Fig. 224).
(3) Disconnect cable retainer from throttle body
bracket (Fig. 224).
Fig. 223 Torque Converter Clutch Solenoid and Regulator/Control Valves
1 - CONVERTER PRESSURE CONTROL VALVE 3 - SCREW (3) 5 - REGULATOR VALVE THROTTLE PRESSURE
PLUG
2 - END COVER 4 - REGULATOR VALVE THROTTLE PRESSURE
PLUG SPRING 6 - SWITCH VALVE
Fig. 224 Throttle Valve Cable at Throttle Body
1 - THROTTLE VALVE CABLE CLIP
2 - THROTTLE BODY LEVER
3 - CABLE RETAINER
21 - 120 31TH AUTOMATIC TRANSAXLERS
SOLENOID - TCC (Continued)
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(4) Disconnect cable from throttle valve lever at
transaxle (Fig. 225).
(5) Disconnect cable retainer at transaxle bracket
(Fig. 225).
INSTALLATION
(1) Install throttle valve cable to bracket at trans-
axle (Fig. 226). Connect cable to transaxle throttle
valve lever.
(2) Route cable through center of intake manifold
(#2 & #3) runners.
(3) Connect throttle valve cable retainer to throttle
body bracket (Fig. 227).
(4) Connect cable core clip to throttle lever (Fig.
227).
(5) Adjust throttle valve cable. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
31TH/THROTTLE VALVE CABLE - ADJUST-
MENTS)
(6) Connect battery negative cable.
Fig. 225 Throttle Valve Cable at Transaxle
1 - LEVER
2 - BRACKET
3 - THROTTLE VALVE CABLE
Fig. 226 Throttle Valve Cable at Transaxle
1 - LEVER
2 - BRACKET
3 - THROTTLE VALVE CABLE
Fig. 227 Throttle Valve Cable at Throttle Body
1 - THROTTLE VALVE CABLE CLIP
2 - THROTTLE BODY LEVER
3 - CABLE RETAINER
RS31TH AUTOMATIC TRANSAXLE21 - 121
THROTTLE VALVE CABLE (Continued)
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ADJUSTMENTS
THROTTLE VALVE LINKAGE ADJUSTMENT
The throttle valve linkage adjustment is very
important to proper transaxle operation. This adjust-
ment positions a valve which controls shift speed,
shift quality, and part throttle downshift sensitivity.
If the setting is too short, early shifts and slippage
between shifts may occur. If the setting is too long,
shifts may be delayed and part throttle downshifts
may be very sensitive.
LINKAGE ADJUSTMENT PROCEDURE
(1) Perform transaxle throttle valve linkage
adjustment while engine is at normal operating tem-
perature.
(2) Using small screwdriver, disengage adjustment
lock at transaxle.
(3) Rotate lever at transaxle all the way to the left
side of vehicle against stop.
(4) Slide cable adjuster until cable core end
touches clip at throttle valve lever.
(5) Press adjuster lock (Fig. 228) to retain setting.
TORQUE CONVERTER
DESCRIPTION
The torque converter (Fig. 229) is a hydraulic
device that couples the engine crankshaft to the
transmission. The torque converter consists of an
outer shell with an internal turbine, a stator, an
overrunning clutch, an impeller and an electronically
applied converter clutch. The converter clutch pro-
vides reduced engine speed and greater fuel economy
when engaged. Clutch engagement also provides
reduced transmission fluid temperatures. The con-
verter clutch engages in third gear. The torque con-
verter hub drives the transmission oil (fluid) pump.
The torque converter is a sealed, welded unit that
is not repairable and is serviced as an assembly.
CAUTION: The torque converter must be replaced if
a transmission failure resulted in large amounts of
metal or fiber contamination in the fluid. If the fluid
is contaminated, flush the fluid cooler and lines.
Fig. 228 Throttle Valve Cable Adjustment Lock
1 - ADJUSTER LOCK
Fig. 229 Torque Converter Assembly
1 - TURBINE
2 - IMPELLER
3 - HUB
4-STATOR
5 - CONVERTER CLUTCH DISC
6 - DRIVE PLATE
21 - 122 31TH AUTOMATIC TRANSAXLERS
THROTTLE VALVE CABLE (Continued)
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Page 1680 of 2399
IMPELLER
The impeller (Fig. 230) is an integral part of the
converter housing. The impeller consists of curved
blades placed radially along the inside of the housing
on the transmission side of the converter. As the con-
verter housing is rotated by the engine, so is the
impeller, because they are one and the same and are
the driving member of the system.
Fig. 230 Impeller
1 - ENGINE FLEXPLATE 4 - ENGINE ROTATION
2 - OIL FLOW FROM IMPELLER SECTION INTO TURBINE
SECTION5 - ENGINE ROTATION
3 - IMPELLER VANES AND COVER ARE INTEGRAL
RS31TH AUTOMATIC TRANSAXLE21 - 123
TORQUE CONVERTER (Continued)
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