7A2-144 TRANSMISSION CONTROL SYSTEM (JR405E)
The JR405E automatic transmission is electrically
controlled by a transmission control module (TCM).
There are four forward speeds and one reverse speed.
This JR405E automatic transmission employs a clutch
pressure direct control system (Direct Electronic Shift
Control: DESC) using duty cycle type solenoid valves,
which ensure high shift quality. This transmission also
has a learning function and constantly checks the time
of each clutch and brake required for the shift in order
to match this time with the target value for the optimum
shift. The TCM will automatically select the most
appropriate shift points and lock-up points depending
on the accelerator pedal opening, the vehicle speed
and the vehicle load. If any trouble arises in the speed
sensor, solenoid valve, etc., the fail-safe control
function is activated to keep the running performance.
The JR405E automatic transmission consists of the
torque converter, oil pump, input shaft, out put shaft,
planetary gears and valve body. The gear train consists
of two planetary gear sets and three multiple plate
clutches in combination with two multiple plate brakes
and a one-way clutch.
Transmission Component Description
Torque Converter
Legend
1. Pump impeller
2. Turbine runner
3. Stator
4. Converter front cover
5. One-way clutch
6. Torque converter clutch (TCC) piston
7. Torsion damper
The torque converter is a device for transmitting the
engine torque to the transmission. It transmits power by
means of oil when the lock up clutch is disengaged,
and by means of a lock up clutch when it is engaged. The torque converter is of the symmetrical, three-
element, single-stage, two-phase type. As shown in the
picture, the symmetrical three-elements refer to three
elements (components) consisting of impeller (1),
turbine (2) and stator (3) that are arranged
symmetrically. Single-stage means that there is only
one turbine as an output element; two-phase means
that the pump impeller acts as a torque converter when
the turbine speed is comparatively low, and as a fluid
coupling when the speed is high. Lock up refers to a
fixed state of the lock up clutch (=torque converter
clutch (TCC) inside the torque converter and thus
connects the engine directly to the transmission.
Oil Pump
Legend 1. Torque converter
2. Oil pump
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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-145
Legend1. Oil pump cover
2. Inner rotor
3. Outer rotor
4. Oil pump housing
The oil pump generating oil pressure is a small sized
trochoid gear type oil pump. It feeds oil to the torque
converter, lubricates the power train mechanism, and
feeds the oil pressure to the oil pressure control unit
under pressure. The oil pump is located behind the
torque converter. Since the inner rotor in the oil pump is
fitted with the drive sleeve of the torque converter, it
works using power from the engine.
Legend
1. Pressure regulator valve
2. Outlet
3. Inlet
When the inner rotor in the oil pump rotates,
transmission fluid is sucked in from the oil pan, passed
between the inner rotor, outer rotor and crescent, and
then discharged. This discharged pressure is sent to
the pressure regulator valve in the valve body, and
adjusted as required for operating the transmission.
The flow rate under pressure increases or decreases in
proportion to the number of rotations.
Input Shaft
The input shaft has some oil holes, through which
lubricating transmission fluid is supplied to the torque
converter, the bearings, etc. The input shaft is fitted to
the turbine runner in the torque converter, the reverse &
high clutch drum and the rear sun gear by means of the
spline. Therefore, the engine driving force received by
the torque converter is transmitted to the reverse &
high clutch drum and rear sun gear.
Output Shaft
The output shaft has some oil holes, through which the
lubricating transmission fluid is supplied to the
bearings, the planetary gear unit, etc. The output shaft
transmits the engine driving force from the planetary
gear to the propeller shaft. The front internal gear is
fitted with the rear carrier assembly by spline. The
parking gear is also fitted by spline. By fixing this gear
mechanically, the output shaft is fixed as required when
parking the vehicle.
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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-151
The transmission fluid temperature (TFT) sensor is part
of the harness assembly. The sensor is a variable
resistor and it measures the temperature of the
transmission fluid. When the TFT sensor is cold, the
sensor resistance is high. When the transmission fluid
temperature increases, the sensor resistance
decreases. With high sensor resistance, the TCM
detects a high voltage on the signal circuit. With lower
sensor resistance, the TCM detects a lower voltage on
the signal circuit.
If the fluid temperature increases to 135 °C (275 °F), the
TCM illuminates A/T Oil Temp lamp on the instrument
panel cluster. When the fluid temperature deceases
below 125 °C (257 °F), the lamp goes off.
Transmission Range (TR) Switch
Legend 1. Input shaft speed (ISS) sensor
2. Output shaft speed (OSS) sensor
3. TR switch
4. In-line harness connector
The transmission range (TR) switch is connected to the
transmission manual shaft and installed externally to
the transmission case. The selector lever moves the
TR switch position via control cable. The TR switch
relays a signal to the TCM indicating transmission
range position by detecting ignition voltage through an
internal switch. Only one of the seven internal switches
will close for each P, R, N, D, 3, 2 and L position.
Normally, the TCM expects to detect one high voltage
input for each position.
The engine will not crank when the selector lever is at
any position other than the P or N range.
Input Shaft Speed (ISS) Sensor
Legend 1. ISS sensor
2. Reverse & high clutch drum
The input shaft speed (ISS) sensor is located on right-
hand of the transmission case. The ISS sensor is a hall
effect element type sensor, which generates a square
wave signal pulse based on the reverse & high clutch
drum rotational speed (32 pulses per a rotation of the
reverse & high clutch drum that is fitted with the input
shaft by spline). The TCM calculates the turbine speed
by the ISS sensor signal, and uses it to calculate torque
converter slip speed and gear ratio.
3
1
24
P
R
N
D
3
2
L
10732485196
1
2
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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-153
TCM Input & Output
TCM Voltage Description
The TCM supplies a buffered voltage to various
switches and sensors. The TCM can do this because
resistance in the TCM is so high in value that a test
lamp may not illuminate when connected to the circuit.
An ordinary shop voltmeter may not give an accurate
reading because the voltmeter input impedance is too
low. Use a 10-megaohm input impedance DMM, to
ensure accurate voltage readings. The input and/ or
output devices in the TCM include analog-to-digital
converters, signal buffers, counters, and special
drivers. The TCM controls most components with
electronic switches which complete a ground circuit
when turned ON.
Electrostatic Discharge Damage
Electronic components used in the TCM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. By comparison, as much as
4,000 volts may be needed for a person to feel even
the zap of a static discharge. There are several ways
for a person to become statically charged. The most
common methods of charging are by friction and
induction.
• An example of charging by friction is a person sliding across a vehicle seat.
Important: To prevent possible electrostatic discharge
damage, follow these guidelines:
• Do not touch the TCM connector pins or soldered components on the TCM circuit board.
• Do not open the replacement part package until the part is ready to be installed.
• Before removing the part from the package, ground the package to a known good ground on
the vehicle.
• If the part has been handled while sliding across the seat, while sitting down from a standing
position, or while walking a distance, touch a
known good ground before installing the part.
• Charge by induction occurs when a person with well insulated shoes stands near a highly charged
object and momentarily touches ground. Charges
of the same polarity are drained off leaving the
person highly charged with opposite polarity.
Sensor inputs
Input shaft speed (ISS) sensor
Output shaft speed (OSS) sensor
Transmission fluid temperature (TFT) sensor
Accelerator pedal position signal (via ECM)
Engine speed signal (via ECM)
Switch inputs
Low & reverse brake transmission fulid
pressure (TFP) switch
2-4 brake transmission fulid pressure (TFP)
switch
High clutch transmission fulid pressure (TFP)
switch
Transmission range (TR) switch
Power drive switch
3rd start switch
Brake pedal switch
4WD low gear signal (via TCCM)
TCM
Solenoid valve outputs
Pressure control (PC) solenoid valve
Torque converter clutch (TCC) solenoid valve
Low & reverse brake solenoid valve
2-4 brake solenoid valve
High clutch solenoid valve
Low clutch solenoid valve
Other outputsVehicle speed signal (2WD only)
CommunicationScan tool
Lamp control outputsCheck trans lamp
A/T oil temp. lamp
Power drive lamp
3rd start lamp
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7A2-158 TRANSMISSION CONTROL SYSTEM (JR405E)
The TCM controls the torque converter clutch (TCC)
solenoid valve based on the accelerator pedal angle,
input shaft speed, output shaft speed and transmission
fluid temperature.
Smooth lock up control is employed to engage or
disengage the TCC smoothly at the time of lock up On
or Off. When the TCM determines the TCC
engagement, the solenoid valve control duty cycle
(pulse width modulation [PWM]) signal is gradually
increased (5% to 95%) and the transmission fluid
between the TCC piston and torque converter front
cover is gradually drained. As a result, the TCC piston
is fitted slowly to the torque converter front cover under
fluid pressure securing smooth lock up engagement. The lock up control does not start when the
transmission fluid temperature is less than 20 °C (68 °F)
even though the vehicle is at the lock up control speed
area. The lock up control disengages when the
accelerator pedal angle is released.
Direct Electronic Shift Control (DECS)
Legend 1. Oil pump
2. Pressure regulator spool valve
3. ON/ OFF type solenoid valve (pressure control [PC]
solenoid valve 4. Duty cycle type solenoid valve (shift solenoid valve)
5. Amplifier (AMP) valve
6. Clutch
Solenoid valve outputs
Pressure control (PC) solenoid valve
Low & reverse brake solenoid valve
2-4 brake solenoid valve
High clutch solenoid valve
Low clutch solenoid valve
TCM
Sensor inputsInput shaft speed (ISS) sensor
Output shaft speed (OSS) sensor
Transmission fluid temperature (TFT) sensor
Accelerator pedal position signal (via ECM)
Engine speed signal (via ECM)
Switch inputs
Low & reverse brake transmission fluid
pressure (TFP) switch
2-4 brake transmission fluid pressure (TFP)
switch
High clutch transmission fluid pressure (TFP)
switch
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ON-VEHICLE SERVICE (JR405E) 7A3-3
Cold Level
The vehicle must not have been driven so that the
temperature reaches around 20 °C (68 °F) before the
cold level check is made.
1. Park the vehicle on a level surface.
2. Apply the parking brake firmly.
3. Start the engine and allow it to warm up.
The engine coolant temperature gauge needle should be midway between the “C” mark and “H”
mark.
4. Let the engine run at idle.
Move the select lever slowly through all the gea
r
ranges.
Stop in each range just long enough for the transmission to engage.
5. Return the select lever either “P” or “N”.
6. Remove the ATF level dipstick.
7. W ipe the dipstick clean with a paper towel.
8. Reinsert the dipstick and wait several seconds.
9. Remove the dipstick.
The ATF level should be inside the “C” range on the dipstick.
If the ATF level is below the “C” range, ATF must be added.
242R300002
ATF CHANGE
1. Park the vehicle on level ground and block the rear
wheels.
2. Start the engine and allow it to idle until the ATF reaches a temperature of 40-50 °C (104-122 °F).
3. Stop the engine.
4. Raise the front to the vehicle and support with suitable safety stands.
5. Remove the drain plug from the oil pan and drain the ATF (approximately 6 liters).
6. Remove the oil pan.
7. Inspect the oil pan (details written below).
8. Install the oil pan.
Note:
Use a new gasket. Clean the oil pan and magnet.
Oil pan bolt torque : 8 N ⋅m (0.8 kgf ⋅m/69 lb ⋅in)
9. Replace the gasket and install the drain plug.
Drain plug torque : 35 N ⋅m (3.6 kgf ⋅m/26 lb ⋅ft)
Note:
Do not reuse the old washer (gasket).
Clean the drain plug (especially the threaded section).
10.Remove the safety stands and wheel blocks.
11.Pour about 5 liters of new ATF.
12. Start the engine. W ith your foot on the brake, move the shift lever through each gear range, and shift to
“P” range.
13.Check the ATF level. Add more ATF carefully as necessary using the dipstick. Refer to “ATF LEVEL”
preciously in this section.
Note:
Keep the engine idle (do not stop it) during the ATF level
adjustment.
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ON-VEHICLE SERVICE (JR405E) 7A3-19
Install or Connect
1. Align the manual valve and the manual plate of the
transmission case.
43ASSY119
2. Install the control valve assembly and tighten the 12 fixing bolts to the specified torque.
Number of bolts Length Color
10 (A) 40 mm (1.57 in) Gold
2 (B) 30 mm (1.18 in) Gold
Bolt torque : 8 N·m (0.8 kgf·m/69 lb·in)
3. Connect the 2 harness connectors.
4. If removed, install the oil strainer.
Refer to “Solenoids, Oil Pressure Switch and Oil Temperature Sensor” previously in this section.
5. Install the new gasket and oil pan.
Bolt torque : 8 N·m (0.8 kgf·m/69 lb·in)
6. Fill with the fluid.
Refer to “ATF CHANGE” in this section.
7. Connect the negative battery cable.
8. Remove the wheel blocks.
FLUSHING THE TRANSMISSION FLUID COOLER AND LINE
The fluid cooler and lines may be flushed under the
following condition. This will help prevent more trouble
after the transmission is repaired.
1. W hen an abnormal amount of debris is found.
2. W hen an abnormal wear or chips on gears and shafts is found while overhauling.
3. W hen there is abnormal clutch facing wear and oil contamination found.
Procedures
1. Block the wheels.
2. Disconnect the negative battery cable.
3. Raise the vehicle and support it with suitable safet
y
stands.
4. Disconnect the fluid cooler lines at the transmission case and fluid cooler.
5. Flush and back-flush the fluid cooler and lines using solvent and compressed air.
Note:
DO NOT exceed (200 kPa/2.0 kgf/cm
2/28 psi) air
pressure, or damage may result to oil cooler.
6. Remove all remaining solvent from the system with
compressed air.
7. Flush the cooling system again with Automatic Transmission Fluid (ATF).
After the final flush, connect all lines.
Cooler line joint connector torque :
44 N·m (4.5 kgf·m/33 lb·ft)
8. Replenish the ATF.
9. Start the engine to test the system for the free flow o
f
fluid. If the flow is restricted, the cooler assembly o
r
lines must be replaced.
Repeated cleaning and flushing may not remove all the debris from the fluid cooler circuit.
Move the select lever through the various ranges and return to neutral.
Check for fluid level.
If the fluid level is below the specified range, ATF must be added.
10. Connect the negative battery cable.
11. Remove the safety stands.
12. Remove the wheel blocks.
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MSG MODEL 7B-7
REMOVAL AND INSTALLATION
Read this Section carefully before performing any removal and installation procedure. This Section gives you
important points as well as the order of operation. Be sure that you understand everything in this Section before you
begin.
Important Operations - Removal
Battery Cable
Disconnect the negative (-) cable from the battery terminal.
Engine Hood
Apply setting marks to the engine hood and the engine hood
hinges before removing the engine hood.
Gear Shift Lever
1. Place the gear shift lever in the neutral position.
2. Remove the gear shift lever knob.
3. Remove the front console assembly.
4. Remove the gear shift lever grommet and dust cover.
5. Remove the gear shift lever cover bolts.
6. Remove the gear shift lever.
Note:
Cover the shift lever hole to prevent the entry of foreign
material into the transmission.
Lifting the Vehicle
1. Jack up the vehicle.
2. Place chassis stands at the front and the rear of the vehicle.
Transmission Oil Draining
1. Remove the transmission oil drain plug.
2. Replace the drain plug after draining the oil.
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