Page 305 of 391
is-7--
1
AUTOMATIC TRANSAXLE
- Transaxle Control21-83I4th
pressureTo end To
2-314-3clutch shift valve
1it2nd3rdpressure
pressure
In 4th Gear
(1) In 4th gear, the front clutch pressure and the kickdown
release pressure are ‘both released, and therefore, the
pressure at the No. 12 port is also released.
(2) Once the pressure starts being released through the No. 12port, the pressure acting on the right end of the plug
(pressure admitted through the No. 18 port) pushes the endclutch valve to the left and holds it in the
same position as
that it has in 3rd gear.
This holds the end clutch engaged.
(3) The
No.8 circuit provides a fail-safe feature which, in the
event of impossibility of
line pressure transaxle to the
No. 18 line from the No.7 line due to improper movementof the end clutch valve by some reasons, allows the line
pressure to have an alternate passage (through the No.8line) to the No. 18 line during
4th gear.
Page 306 of 391
--
I121-84
AUTOMATIC TRANSAXLE - Transaxle Control
jREAR CLUTCH EXHAUST VALVE
j,
iIi
i
cto front
To rearclutchclutchTo kickdown
servo release side
2-3/4-3shift valve
Shift control
solenoid valve
- Aa
Ex
5a
Shift
controlsolenoid
valve
- B
- From l-2shift valve
I
ExThe valve is actuated by the line pressure controlled
by the shift control valve to release the oil pressure
of the rear clutch when shifting
iS performed from3rd to 4th gear. The valve also controls the timing ofthe oil pressure to be supplied to the rear
clutchwhen shifting is performed from 4th to 3rd
gear.preventing shocks from occurring.
Page 307 of 391

AUTOMATIC TRANSAXLE - Transaxle Control21-85
I o 2-314-3shift valveFrom rear
clutch
11 1From N-Dcontrol valve
FromshiftTo manualcontrolvalve
valve
(4thoressure)175011‘
1
>rn 2-314-3jnift valveTCPUE’Check t
I
To shiftcontrol To manualFrom N-Dmntmlvalve
”.,,l”l
(4thvalve
valvepressure)
--
II1111
”
E,Upshift from
3rd to 4th Gear
(1) When the 4th pressure from the shift control valve is
directed to the rear clutch exhaust valve through the No.8
line, it pushes the elements “A” and
“B” of the rear clutch
exhaust valve to the right.
(2) The element “B” of the rear clutch exhaust valve that has
been moved towards the right closes the
No.5~ line port.
This prevents the line pressure coming from the N-D
control valve from being directed to the rear clutch.
(3) The line pressure supplied to the rear clutch is discharged
from the No. 15 line through the No.20 and No.20a lines.
This releases the rear clutch.
Downshift from 4th to
3rd Gear
(1) If the
4th pressure from the shift control valve is dis-
charged, the element “A” of the rear clutch exhaust valve
is pushed to the left under the line pressure established in
the
No.5~ line. This line pressure is directed to the rear
clutch via the No.20 line, No.
20a line, and then No. 15 line.
In one of the passages connecting the No.20 line with the
No. 20a line, there is a check ball and in the other there is anorifice. When one passage is closed by the check ball, the
fluid flows through the other passage with an orifice, which
slows down the fluid flow speed, permitting gradual
transaxle of pressure to the No.20a line to create condi-
tions ready for the rear clutch to operate.
(2) When the
2-3/4-3 shift valve operates and the hydraulic
pressure acts on the front clutch and the release side
chamber of kickdown servo cylinder, the pressure is
directed through the No. 12 line to the right end of the
element
“8” of the clutch exhaust valve.
Combined with the spring force, this pressure pushes the
element “B” of the valve to the left. This allows the high
line pressure in the
No.5~ line to be directly transmitted to
the rear clutch through the No. 15 line.
Page 308 of 391
21-86AUTOMATIC TRANSAXLE - Transaxle Control
SOLENOID VALVEThere are four solenoid valves installed on the valve
bob,,they are activated, as explained previously, by commands from
the transaxle control unit.
Terminal 1
Pressure control solenoid valve
2Damper clutch control solenoid valve
3Shift control solenoid valve “A”
I~-- I4Shift control solenoid valve “6”1
GroundGround
w--------%Pressure control
solenoid valvel
rI
IkI!iiLDamper
clutch
control
solenoid
valve
IShift
control
solenoidivalve-A
;
IShift
control
solenoid
ivalve-B
Connector17wo35
Page 309 of 391
AUTOMATIC TRANSAXLE - ~kmucle ControlHWBRAULIC
ClRCUlT
S.XTOR LEVER IN “N”Torque-converterKickdown servo
FrontRearu)w-reverse =.I 1~
clutchclutchbrakeclutch
r-m I
-amper clutchIhOlJenoid valve
Oil -filter,
IIShi LroI3,
Lii PressureTorque-converter pressureand
lubriition oil pressureReducing pressurePump suction pressure
Lii Pressure(control pressure)
PCSV control pressureDamper clutch pressure
DCCSV control pressure
I1760224
A
Page 310 of 391
21-88AUTOMATIC TRANSAXLE - Transaxle ControlTSELECTOR LEVER IN “P”
icTorque-convertersolenoid valve
I IncFoque-converter
,xmtrol valveIT=7
IIcontrolsolenoidII.- L. .- mlvi-we 0
II
PRNDPLPressure
7ntfol
wpan J
= Line Pressurem Pump suction pressureDamper clutch pressureTorque-converter pressureand lubrication oil
pressurem Line Pressure(control pressure)m DCCSV control prasswe
Reducing pressurem PCSV control pressureI
1750245
.--___~
Page 311 of 391
AUTOMATIC TRANSAXLE - Transaxle Control21-89
.LECTOR LEVER IN “D” (Stopping)Torqueconverter
/Klckdown servoFrontRearLow-reverseEnd
clutchclutchbrakeclutch
---
-Ln
r clutch
\ Mhm+oque-converterontrol
valve
IOil panI
N-Rcontrol valve18
U-D controlfalve
Pressurecontrol valveLine PressureTorque-converter
pressureand Jubrication oil pressureReducing pressurePump suction pressure= Line Pressure(control pressure)
PCSV control pressureDamper clutch pressure
DCCSV control pressure
1760246
Page 312 of 391
21-90AUTOMATIC TRANSAXLE - Transaxle Control
SELECTOR LEVER IN
‘D” (1st Gear)Torque-converterFront
clutch
F1,/
RearLow-reverseEndclutchbrakeclutch
-m -Kickdown servosolenoid
valve
h
N-R control valve
El
U-D controlflalvePressurecontrol
valve
1 Oil panJLine
PressurePump suctiin pressureDamper clutch pressure
Torqueconverter pressureand lubrication oil pressureReducing pressurem Line Pressure(control pressure)
PCSV control pressure
= DCCSV control pressure_
1750247