clutch TOYOTA CAMRY V20 1986 Service Information

RELAYS
INSPECTION OF A/C RELAY
1. REMOVE COVER OF RELAY BOX
2. REMOVE RELAY
3. INSPECT RELAY CONTINUITY
(Magnetic Clutch Relay)
If continuity is not as specified, replace the relay.
(A/C Fan Relay No. 3)If continuity is not as specified, replace the relay.
If continuity is not as specified, replace the
relay.
Apply battery voltage to
terminal 2 (±j and 6 (+)Apply battery voltage to
terminal 1 and 3
Apply battery ±voltage to
terminal 1 and 3
(A/C Fan Relay No. 2)
Condition
ConditionCondition
Terminal
Terminal
Terminal
Constant
ConstantConstant
± AIR CONDITIONING SYSTEMRelaysAC±37

A140L Automatic Transaxle
CONSTRUCTION AND OPERATION
The A140L automatic transaxle can be roughly divided into the automatic transmission section and the
differential section. The automatic transmission section is composed of the torque converter, planetary
gear unit and the hydraulic control system.
OPERATION
The pump impeller is rotated by the engine, which
causes a flow in the ATF inside the torque converter.
The flow of ATF caused by the pump impeller strikes
the turbine runner, providing a force to rotate the tur-
bine runner, and transmits torque to the input shaft.
The flow of ATF which has hit the turbine runner re-
bounds and tries to flow in the direction opposite to
the direction of rotation of the pump impeller, but the
stator returns the flow the original direction of rotation.
So the ATF
becomes a force which supports the pump impeller
and increases torque.
HINT: Although the stator is immobilized by the one-
way clutch, should the one±way clutch become de-
fective the stator will be rotated by the flow of ATF,
the flow of
ATF will not be reversed, torque will not be increased
and the problem of inadequate acceleration will occur.
The lock±up clutch is pushed against the front cover
by fluid pressure so that the engine revolutions are
directly transmitted to the input shaft without the me-
dium of the
AT F.
1. Torque Converter
CONSTRUCTION
The torque converter is composed of the pump impeller
which is rotated by the engine, the turbine runner and
lock±up clutch which are fixed to the transmission input
shaft, and the stator which is attached to the stator
shaft via the one±way clutch.
The torque converter is filled with ATF.
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±5

2. Planetary Gear Unit
CONSTRUCTION
The planetary gear unit is composed of three sets of planetary gears, three clutches which transmit
power to the planetary gears, and four brakes and three one±way clutches which immobilize the
planetary carrier and planetary sun gear.
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±6

OPERATION
Power from the engine transmitted to the input shaft via the torque converter is then trans-
mitted to the planetary gears by the operation of the clutch.
By operation of the brake and one±way clutch, either the planetary carrier or the planetary sun
gear are immobilized, altering the speed of revolution of the. planetary gear unit.
Shift change is carried out by altering the combination of clutch and brake operation.
Each clutch and brake operates by hydraulic pressure; gear position is decided according to
the throttle opening angle and vehicle speed, and shift change automatically occurs.
The conditions of operation for each gear position are shown on the following illustrations:
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±7

3. Hydraulic Control System
CONSTRUCTION
The hydraulic control is composed of an oil pump, rotated by the engine, which supplies hydraulic pres-
sure; a valve body which controls the hydraulic pressure and the opening and closing of the fluid pas-
saged; and a governor valve which supplies hydraulic pressure in accordance with vehicle speed.
OPERATION
Hydraulic pressure supplied by the oil pump is controlled± by the regulator valve; the resulting oil pres-
sure controlled by the regulator valve is called the line pressure.
Line pressure produces the hydraulic pressure for throttle pressure and governor pressure. Also, line
pressure produces hydraulic pressure for the operation of each brake and clutch in the planetary gear
unit.
The throttle valve acts to produce hydraulic pressure, called the throttle pressure, which responds to ac-
celerator pedal modulation. Throttle pressure increases as the accelerator pedal is depressed.
The governor valve produces hydraulic pressure, called the governor pressure, in response to vehicle
speed. Governor pressure increases as vehicle speed increases.
In accordance with the difference between throttle pressure and governor pressure, each shift valve
shifts, the fluid passages to the clutches are brakes in the planetary gear unit are opened and the
clutches and brakes operate, and shift change occurs.
The operation of the hydraulic control system, using the 2±3 shift valve as an example, is shown below;
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±8

A140E Automatic Transaxle (ECT)
WHAT IS THE ECT?
ECT means Electronic Controlled Transaxle. The hydraulic control system of the previous automatic
transaxle has been changed, the throttle and governor pressure have been replaced by electronic
signals and a micro computer has been used to give precise control of shift timing and lock±up tim-
ing.
FEATURES OF THE ECT
(a) The shift pattern can be chosen.
In the ECT ECU micro computer used in the A140E, two types of shift pattern, Power and Normal,
are recorded in the memory. By operating the pattern select switch, the driver can select the pre-
ferred shift pattern.
(b) Reduced fuel consumption and reduced shock during shifting is made possible.
Precise control of the shift timing by the ECT ECU, operation of the lock±up clutch from low speeds,
and decreased fuel consumption are made possible. Also, shock during Shifting is reduced.
(e) Self±Diagnostic System
When a malfunction occurs in the electronic control system, the driver is informed of this fact. Also,
there is a Self±Diagnostic System which displays the location of the malfunction when the service
connector is shorted.
(d) Fail±Safe System
A fail±Safe System is included so that, even if a malfunction occurs in the electronic control system,
the vehicle will be able to operate.
CONSTRUCTION AND OPERATION
When the A140E (ECT) is compared with the A140L, the automatic transaxle body has the same
construction and operation, with the exception of the hydraulic control system, as the A140L.
The electronic control system, which controls the shift timing and lock±up timing, has been added.
1. Hydraulic Control System (Comparison with the A140L)
VALVE BODY ± Additions or changes to solenoid valve
In the A140E there are three solenoid valves, the No. 1, the No. 2 and the lock±up solenoid valves.
Shifting occurs according to whether the No. 1 and No. 2 solenoid valves are ON or OFF, and the
lock±up solenoid valve controls the lock±up clutch.
GOVERNOR VALVE ± Removed
With the A140E, the governor valve has been replaced with a speed sensor, so that instead of the
governor pressure, a speed sensor signal is sent to the ECT ECU.
SHIFT CONTROL IN ECT
1. The vehicle speed is sensed by the vehicle speed
sensor, which sends this data to the
ECU in the form of electrical signals.
2. The angle to which the throttle is open is sensed
by the throttle position sensor, which sends this
data to the ECU in the form of electrical signals.
3. The ECT computer determines the shift point on
the basis of these two signals and operates the
solenoid valves in the hydraulic control unit, thus
shifting the transmission.
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±9

2. Electronic Control System
COMPONENTS
The electronic control system for controlling the shift timing and the operation of the lock±up clutch
is composed of the following three parts:
(a) Sensors: These sense the vehicle speed and throttle position and send this data to the ECT ECU
in the form of electronic signals.
(b) ECT ECU: This determines the shift and lock±up timing based upon the signals from the. sensors.
(e) Actuators: Solenoid valves divert hydraulic pressure from one circuit of the hydraulic control unit
to another, thus controlling shifting and lock±up timing.
VEHICLE SPEED SENSOR
NO. 1 AND NO. 2
BRAKE LIGHT SWITCH
O/D MAIN SWITCH
THROTTLE POSITION
SENSOR
CRUISE CONTROL
COMPUTER PATTERN SELECT
SWITCH
NEUTRAL START
SWITCH
LOCK±UP SOLE±
NOID VALVE NO. 2 SOLENOID
VA LV E NO. 1 SOLENOID
VA LV E
Control of shift
tinning
Self±diagnostic
systemControl of lock±up
timing
WATER TEMP.
SENSORO/D OFF INDI±
CATOR LIGHT Back±up system
ECT ECU
ENGINE
ECU
ACTUATOR
SENSOR ACTUATOR
± AUTOMATIC TRANSAXLEDescription (A140L and A140E)AT±10

Operating Mechanism for Each Gear (A140L A140E)
1. CLUTCH BRAKE AND ONE±WAY CLUTCH
'Down±shift only ± no up±shift `Down±shift only ± no up±shift
Shift lever
position Shift lever
positionGear position
Gear Position
Parking Parking
Reverse
A140L
Reverse
A140E
Neutral Neutral
2nd2nd
3rdO/D
O/D2nd
2nd2nd
1 st
2nd1 st
1 st3rd
1 st1 st
3rd
± AUTOMATIC TRANSAXLETroubleshooting (Operating Mechanism ± for Each Gear)
(A140L and A140E)AT±14

3. INSPECT EACH UP±SHIFT POSITION
(a) Warm up the engine.
Coolant temperature: 176
°F (80°C)
(b) Turn the O/D switch to ºONº.
(c) Place the pattern select switch in ºNormalº and the shift
lever into the D range.
(d) During a road test (above 10 km/h or 6 mph) check that
voltage at the ECT terminal is as indicated below for
each up±shift position.
If the voltage rises from 0V to 7V in the sequence
shown, the control system is okay.
The chart on the left shows the voltmeter reading and
corresponding gears. .
HINT: Determine the gear position by a light shock or
change in engine rpm when shifting. The lock±up clutch
will turn ON only infrequently during normal 2nd and 3rd
gear operation. To trigger this action, press the acceler-
ator pedal to 50% or more of its stroke. At less than
50%, the voltage may change in the sequence 2V ± 4V
± 6V ± 7V. 2. INSPECT BRAKE SIGNAL
(a) Depress the accelerator pedal until the ECT terminal
indicates 8V.
(b) Depress the brake pedal and check the voltage read-
ing from the ECT terminal.
(c) Brake pedal depressed . . . . . . . . . . 0V
Brake pedal released . . . . . . . . . . . . 8V
If not as indicated, there is a malfunction in either the
stop light switch or circuit.
INSPECTION OF Tt TERMINAL VOLTAGE
1. INSPECT THROTTLE POSITION SENSOR SIGNAL
(a) Turn the ignition switch to ON. Do not start the engine.
(b) Connect a voltmeter to terminals Tt and E1.
(c) While slowly depressing the accelerator pedal,
check that ECT terminal voltage rises in sequence.
if the voltage does not change in proportion to the
throttle opening angle, there is a malfunction in the
throttle position sensor or circuit.
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±31

Mechanical System Tests
STALL TEST
The object of this test is to check the overall performance of the transaxle and engine by measur-
ing the stall speeds in the D and R ranges.
CAUTION:
wPerform the test at normal operation fluid temperature (122 ± 176°F or 50 ± 80°C).
wDo not continuously run this test longer than 5 seconds.
wTo ensure safety, conduct this test in a wide, clear, level area, which provides good traction.
wThe stall test should always be carried out in pairs. One should observe the conditions of wheels
or wheel stoppers outside the vehicle while the other is performing the test.
MEASURE STALL SPEED
(a) Chock the front and rear wheels.
(b) Connect a tachometer to the engine.
(c) Fully apply the parking brake.
(d) Step down strongly on the brake pedal with your left foot.
(e) Start the engine.
(f) Shift into the D range. Step all the way down on the accelerator pedal with your right foot. Quickly
read the stall speed at this time.
Stall speed: 2,200
+150 rpm
(g) Perform the same test in R range.
EVALUATION
(a) If the stall speed is the same for both ranges without the rear wheels rotating but lower than specified
value:
wEngine output may be insufficient
w Stator one±way clutch is not operating properly
(b) If the stall speed in D range is higher than specified:
wLine pressure too low
wForward clutch slipping
wNo. 2 one±way clutch not operating properly
wO/D one±way clutch not operating properly
(c) If the stall speed in R range is higher than specified:
wLine pressure too low
wDirect clutch slipping
wFirst and reverse brake slipping
wO/D one±way clutch not operating properly
(d) If the stall speed in both R and D ranges are higher than specified:
wLine pressure too low
wImproper fluid level
wO/D one±way clutch not operating properly
± AUTOMATIC TRANSAXLETroubleshooting (Mechanical System Tests) (A140L and
A140E)AT±38