Stall Speed
Test
CAUTION:
. To prev€nt transmission damage, do not t6st stall speed for more than ro sgconds at a time.. Do not shift the levor while raising the engine speed.. Bo sule lo remove the pressure gauge betoro testing stall speed.
'1. Engage the parking brake, and block the front wheels.
2. Connect a tachometer to the engine, and start the engine.
3. Make sure the Ay'C switch is OFF.
4. After the engine has warmed up to normal operating temperature (the radiator fan comes on). shift into E position.
5. Fully depress the brake pedal and accelerator for 6 to g seconds, and note engine speed.
6. Allow two minutes for cooling, then repeat the test in @ and @ positions.
NOTE:
. Stall speed tests should be used for diagnostic purposes only,. Stall speed should be the same in o., E and E positions.
Stall Spsed RPM:
Specification: 2.700 rpm
Service Limit: 2,550 - 2,850 rDm
TROUBLEPROBABLE CAUSE
. Low fluid level or ATF pump outDur. Clogged ATF strainer. Pressure regulator valve sluck closeo. Slipping clutch
. Slippage of 4th ctutch
. Slippage of 2nd clutch
. Slippage of lst clut"tr or. t"t g""io*-*"y "lut"h
Stall rpm high in D., E and E positions
Stall rpm high in El position
Stall rpm high in E posirion
Stall rpm high in E position
Stall rpm low in LDa . El and E positrons. Engine output low. Torque converter one-way clutch slipping
14-116
Description
(cont'd)
Gear Sel€stion
The shift lever has six positions: @ pARK, E REVERSE, E NEUTRAL, E DR|VE, g SECOND, and El LOW.
Staning is possible only in E and E positions through the use of a slid6-type, neutrafsafety switch.
Automrtic Transaxle {A/T} Gear Position Indicltor
The A-lT gear position indicator in the instrument panel shows which gear has been selected without having to look downat the console.
PoshionDe3cription
E PARK
E REVEBSE
E NEUTRAL
D DRIVE
E SECOND
E LOW
Front wheels locked; park pawl engaged with the park gear on the driven pulley shaft. The startclutch and the forward clutch released.
Reverse; reverse brake engaged.
Neutral; the start clutch and the forward clutch released.
General driving; the transmission automatically adjusts to keep the engine at the best speed fordriving conditions.
For rapid accelsration at highway speeds; the transmission shifts into a lower range of ratios forbetter acceleration and increased engine braking.
For engine braking and power for climbinO; the transmission shifts into the lowest range of theralros.
l-
14-196
Description
Clutches/Reverse Brake/Planetary Gear/Pulleys
Clulches/Reverse Brake
The CVT uses the hydraulically-actuated clutches and brake to engage or disengage the transmission gears. When
hydraulic pressure is introduced into the clutch drum and the reverse brake piston cavity, the clutch piston and the reverse
brake piston move. This presses the friction djscs and the steel plates together, locking them so they don't slip. Power is
then transmitted through the engaged clutch pack to its hub-mounted gear. and through engaged ring gear to pinion
gears.
Likewise, when the hydraulic pressure is bled from the clutch pack and the reverse brake piston cavity, the piston releases
the friction discs and the steel plates, and they are free to slide past each. This allows the gear to spin independently on its
shaft, transmitting no power.
Start Clutch
The start clutch, which is located at the end of the driven pulley shaft, engages/disengages the secondary drive gear.
The start clutch is supplied hydraulic pressure by its ATF feed pipes within the driven pulley shaft.
Forward Clutch
The forward clutch, which is located at the end of the drive pulley shaft, engages/disengages the sun gear.
The forward clutch is supplied hydraulic pressure by its ATF feed pipe within the drive pulley shaft.
Reverse Brake
The reverse brake, which is located inside the inte.mediate housing around the ring gear, locks the ring gear in E posi-
tion. The reverse brake discs are mounted to the ring gear and the reverse brake plates are mounted to the intermediate
housing. The reverse brake is supplied hydraulic pressure by a circuit connected to the internal hydraulic circuit.
Planetary Gear
The planetary gear consists of a sun gear, a carrier assembly, and a ring gear. The sun gear is connected to the input shaft
with splines. The pinion gears are mounted to the carrier which is mounted to the fo.ward clutch drum. The sun gear
inputs the engine power via the input shaft to the planetary gear, and the carrier outputs the engine power. The ring gear
is only used for switching the rotation direction of the pullev shafts,
In E. E, and E positions (forward range), the pinion gears don't rotate and revolve with the sun gear, so the carrier
rotates. In E] positjon {reverse range), the reverse brake locks the ring gear and the sun gear drives the pinion gears to
rotate. The pinion gears rotate and revolve in the opposite direction from the rotation direction of the sun gear, and the
carrier rotates with pinion gear revolution.
Pulleys
Each pulley consists of a movable face and a fixed face, and the effective pulley .atio changes with engine speed. The
drive pulley and the driven pulley are linked by the steel belt.
To achieve a low pulley ratio, high hydraulic pressure works on the movable face of the driven pulley and reduces the
effective diameter of the drive pulley. and a lower hydraulic pressure works on the movable face of the drive pulley to
eliminate the steel belt slippage. To achieve a high pulley ratio, high hydraulic pressure works on the movable face of the
drive pulley and reduces the eifective diameter of the driven pulley, and a lower hydraulic pressure works on the movable
face of the driven pulley to eliminate the steel belt slippage.
b
14-198
Description
Electronic Control System ('99 - 00 Modelsl (cont'dl
Grade Logic Control System
How it works:
The PcM compares actual driving conditions with memorized driving conditions. based on the input from the vehiclespeed sensor, the throttle position sensor, the manifold absolute pressure sensor, the engine coolant temperature sensor,the brake switch signal, and the shift lever position signal, to control shifting while the vehicle is ascending or descendinga slope.
Ascending Control
When the PCM determines that the vehicle is climbing a hill in E position, the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. so the vehicle can run smooth and have more powerwhen needed. There are three ascending modes with different shift schedules according to the magnitude ot a gradient inthe PCM.
Descending Control
when the PCM determines that the vehicle is going down a hill in E position. the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. This, in combinstion with engine braking, achievessmooth driving when the vehicle is descending, There are three descending modes with different shift schedules accord-ing to the magnitude of a gradient in the PCM.
L
14-206
Component Locations
36 - 98 Models
BRAKE SWITCH
DRIVEN PULLEYSPEED SENSOR
INHIBITOR SOLENOID
ENGINE CONTROLMODULE IECMI
SECONDARY GEAR SHAFTSPEEO SENSOR
AUTOMATIC TRANSAXLE (A/T}GEAR POSITION SWITCI{
MANIFOLD ABSOLUTE
VEHICLE SPEEO SENSOR{vss}
IMAPI SENSOR
THROTTI.I POSITION {TPISENSOR
PH.PL CONTROLLINEAR SOLENOID
/i/ i,' / ,','4
,i/:1
t"--.---.- i,,
-_,-:-_a.--:
il
START CLUTCH CONTROLLINEAR SOLENOIDPULLEY
SHIFT CONTROLLINEAR SOLENOTD
$r,
14-224
h
SPEED SENSOR
TCM CONNECTOR B (22P}
Terminal NumbelSignalDescriptionMeasuring Conditions/Terminal Voltage
B1SOL INHInhibitor solenoid controlWith inhibitor solenoid ON: Baftery voltage
With inhibitor solenoid OFF: 0 V
82MAP (PB)-M an if old Absol r-rte Pressure IMAP)
sensor signal inPUtWith iqnition switch ON (ll): Approx.2.5 V
With e;gine adling: Approx. 1.0 V (depending on
engine speed)
B3Not used
B4TPS-Throttle Position (TP) sensor signal
input
With ignition switch ON (ll) and throftle fully open:
4.14 - 4.42 VWith ignition switch ON (ll) and throttle fully
closed: 0.44 - 0.56 V
VSSVehicle Speed Sensor (VSS) signal
Inpur
With ignition switch ON (ll) and rotating front
wheelsr 0-5Vcycle
TMBData communication with ECM:
Transmission control data outpUt
With ignilion swltch UN lll): rulslng slgnar
81TMAData communication with EClvl:
PGM Fl control data inPut
With ignition swltch uN {ll,: l-ulslng slgnal
B8NDN SGDriven pulley speed sensor ground
B9NDNDriven pulley speed sensor signal
input
ln other thTnE and E position: Pulsing signal
810NDRDrive pulley speed sensor signal
Input
-tn ottrer ttran E ana E position: Pulsing signal
811Not used
812STOP SWBrake switch signal inPutWith brake pedal depressed: Battery voltage
With brake pedal released: 0 V
813DIAG-H(TXD/RXD)Data communication:Diagnostic trouble code outPut
Wittr ignitio.r s*itct' ON (ll): Approx 5.0 V
814Se-ice ctrect signatWith ignition switch ON (ll) and service check
connector oPen: APProx.5 V
With iqnition switch ON (ll) and service check
"onn"itot. connect"d with special tool: 0 V
Secondary gear shaft speed sensor
signal input
Depending on vehicle speed: Pulsing signal
When vehicle is stoPped: 0 V815VEL
816VEL SGSecondary gear shaft speed sensorgrouno
817NDR SGDrive pulley speed sensor ground
818HBRK SWParking brake switch signal inPutWith parking brake lever pulledr 0 V
With parking brake lever released: Battery voltage
819Not used
B 20VREF+5 V relerenceWith ignition switch ON (ll): Approx 5 V
821Not used
Not used
PGM Terminal Voltage/Measuring Conditions ('99 - 00 Modelsl
A/T Control System
The PCM terminal voltage and measuring conditions are shown for the connector terminals that are related to the A/T con-trol system. The other PCM terminal voltage and measuring conditions are described in section 11.
PICM Connoctor Terminrl Location3
Terminal NumberSignalDescriplionMeasuring Condhions/Torminal Voltage
A7ATP DA,/T gear position switch
E position input
InEposition:OV
In other than E] position: Approx. 1O V
A9ATP NPA/T gear position switch
@ and S positions input
In E and El positions: 0 V
In other than E] and E position: Approx. 1O V
A10Timing and adjustment service
check signal
With ignition switch ON {ll} and service check
connector oDen: 5 V
With ignition switch ON (ll) and service check
connector connected with soecialtool:0 v
ATP LA,/T gear position switch
I position input
In E position; OV
In other than E position: Approx. 10 V
STOP SWBrake switch signal outputBrake pedal depressed: Battery voltage
Brake pedal released: 0 V
PCM CONNECTOR B I25P}
Terminal NumberSignalDescriptionMoasuring Condhions/Terminal Vohage
B1IGPlPower supply circuit from main
relay
With ignition switch ON (lll: Battery voltage
With ignition switch OFF: 0 V
82PG1Ground
B8HLC LSMPH-PL control linear solenoidpower supply neqative electrode
B9IGP2Power supply circuit from main
relay
With ignition switch ON (lll: Battery voltage
With ignition switch OFF:0 V
810PG2Ground
817HLC LSPPH-PL control linear solenoid
power supplypositive electrode
With ignition switch ON {ll): Pulsing signal
818SC LSMStart clutch control linear
solenoid power supply negative
electrode
s20LGIGround
821VBUBack-up power supplyAlways battery voltage
B22Ground
825SC LSPStan clutch control linear
solenoid power supply positive
electrode
With ignition switch ON (ll): Pulsing signal
t
14-232
Troubleshooting Flowchart - Vehicle Speed Sensor (VSS)
NOTE: Record all freeze data before you troubleshoot'
Po$rible Ctuse
. Disconnected vehicle speed
sensor (VSS) connectol. Short or open in VSS wire' Faulty VSS
@. Make sure lifts, iacks, and sal€tY stands are placed properly lsoe section 1)'
. Set the parking brake securelv, and block the rear wheels'
. iacr upile rront or the vehicle, and support it with safety st'nds'
TCM CONNECTORS
Wire side of female terminals
. OBD ll Scan Tool indicates Code
P1791.. Setf-diagno3is E indicato. light
blinks tour times.
Refer to seclion 23 for vehicle
soeed sensor IVSSI test
Check the VSS Voltage:
1. Raise the vehicle2. Shift the transmission to lEposrtlon.3. Disconnect the A (26P) and B(22P) connectors from the
TCM.4. Turn the ignition switch ON {ll).
5. Rotate the front wheel and
check for the voltage between
the 85 and 413 or A26 termi-
nals. Block the other wheel so
at does not turn
Check for oP€n in the wire
between the 85 terminal and the
vehicle speed sensor {VSS}. lf
wire is OK, check the vSS (see
soction 23).
Does0Vandapprox 5 V or more
appear alternatelY?
Check for loos€ TCM connedors
lI nec€ssary, substitute a known'
good TCM and recheck.
14-243