UNIT REPAIR (AW30–40LE) 7A4–81
Disassembly
1. Remove second brake assembly from output shaft.
246RY00014
2. Remove oil seal ring from output shaft.
247RY00028
3. Remove the seven discs, seven plates and flange(B–3). 4. Remove rear planetary gear from rear planetary ring
gear.
247RY00029
5. Check operation of No.2 one-way clutch.Hold the planetary gear and turn the one-way clutch
inner race.
The one-way clutch inner race should turn freely
counterclockwise and should lock clockwise.
RUW37ASH004701
En dOFCallout
Legend
(1) Lock
(2) Free
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
CONSTRUCTION AND FUNCTION 7A1-3
DESCRIPTION
CONSTRUCTION
1 Converter Housing 6 Low Clutch 11 Oil Pump
2 Torque Converter 7 Low & Reverse Brake 12 Control Valve
3 High Clutch 8 Output Shaft 13 Low One-way Clutch
4 Reverse Clutch 9 Extension Housing 14 Parking Gear
5 2-4 Brake 10 Input Shaft
Figure 1. Construction of Automatic Transmission
The JR405E automatic transmission is electrically controlled by a microcomputer 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 solenoids, 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, APP sensor, solenoid, etc., the fail-safe control function is activated
to keep the running performance.
Problems with the sensors or the solenoids can quickly be detected with the self diagnosis procedure
described in this manual.
The JR405E automatic transmission consists of the torque converter, oil pump, input shaft, out put shaft,
planetary gears and control valves.
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.
2WD
4WD
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A1-6 CONSTRUCTION AND FUNCTION
ELECTRONIC CONTROL COMPONENTS LOCATION
4WD Only 4W D Only
Instrument panel (Meter)
Speed meter (2WD Only)
Shift position indicator lamp
POWER DRIVE, 3rd START
indicator lamp
A/T OIL TEMP indicator lamp
CHECK TRANS indicator lam
p
Brake pedal
Brake Switch
Transmission Control Module (TCM)
Electrical source
Ignition
Battery voltage
Speed sensor
Turbine sensor
Inhibitor switch
ATF thermo sensor
High clutch oil pressure switch
2-4 brake oil pressure switch
Low & Reverse brake oil pressure
switch
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & Reverse brake solenoid
Lock-up solenoid
Transmission
Transfer Control Module
Transfer
4L mode switch
Engine
Engine speed sensor
Accelerator pedal Position Sensor
Engine Control Module (ECM)
Data link connector
Select lever
Power Drive
, 3rd Start select switch
Figure 3. Electronic Control Components Location
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
CONSTRUCTION AND FUNCTION 7A1-11
• The JR405E consists of two sets of planetary gears, which are called front planetary gear and rear
planetary gear.
• The sun gear of the front planetary gear is fixed to the drive plates of 2-4 brake and reverse clutch.
• The planetary carrier of the front planetary gear is fixed to the drum of the low clutch, the drive plates of
the low & reverse brake, and the hub of the high clutch.
• The internal gear of the front planetary gear, and the planetary carrier of the rear planetary gear, are
connected as one and fixed to the output shaft.
• The sun gear of the rear planetary gear is fixed to the input shaft.
• The internal gear of the rear planetary gear is fixed to the hub of the low clutch.
Clutch and Brake • Basic structure of the clutch and brake is shown in the figures below.
• In the figure A, the clutch plates (drive plate and driven plate) are released so that they slip against each
other, transmitting no power.
• Figure B shows the condition where the oil pressure is acting on the piston. The clutch plates are fitted
to each other under pressure, transmitting the rotations of the clutch drum to the clutch hub.
• When the oil pressure is removed from the piston, the clutch returns to the condition in figure A via the
return spring.
Figure 13. Basic Construction of Clutch and Brake
Low Clutch, High Clutch and Reverse Clutch (Multi-Plate Clutch) • The multi-plate clutch is composed of drive plates and driven plates. By applying the oil pressure onto
the end surface of the plates, the clutch is engaged. The oil pressure is adjusted with the control valve
according to the signal from the TCM.
• All clutches use dish plates to prevent uncontrolled operation of the clutches when engaged, causing a
shock.
• For the reverse clutch, a piston check ball is used to release the oil pressure. This prevents clutch drag
caused by oil pressure generated by residual ATF due to the centrifugal force while the clutch is racing
(under no oil pressure).
• For the low clutch and high clutch, a centrifugal balance chamber full of ATF is provided to offset the
excessive oil pressure. This prevents clutch drag caused by oil pressure generated by residual ATF due
to the centrifugal force while the clutch is racing (under no oil pressure).
• The solenoid in the control valve is driven based on the shift signal from TCM, it moves the shift valve,
thereby engaging the drive plate and driven plate through the piston of each clutch.
• As a result, elements of the planetary gear unit are combined.
• When the oil pressure is removed, the piston returns to the original position via the force of the return
spring.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
CONSTRUCTION AND FUNCTION 7A1-25
TRANSMISSION CONTROL MODULE (TCM)
• The TCM is fitted on the side of the brake pedal via two stud bolts.
• The TCM judges the line pressure, gear shifting point and lock-up operation based on electrical signals
from switches and sensors, and sends the appropriate signals to solenoids.
B9 B8 B7 B6 B5 B4 B3 B2 B1 A9 A8 A7 A6 A5 A4 A3 A2 A1
B18 B17 B16 B15 B14 B13 B12 B11 B10 A18 A17 A16 A15 A14 A13 A12 A11 A10
B24 B23 B22 B21 B20 B19 A24 A23 A22 A21 A20 A19
Connect to White Connector Connect to Grey Connector
Figure 49. Pin Assignment
Pin No. Pin Assignment Pin No.Pin Assignment
B1 2-4 Brake Oil Pressure Switch A1 V BATT (Battery Back-up Power Supply)
B2 2 Position Switch A2 P Position Switch
B3 Turbine Sensor A3 Brake Switch
B4 ATF Thermo Sensor A4 3rd Start Indicator Lamp
B5 Ground A5 K-Line Signal (Tech 2 Serial Communication)
B6 Low & Reverse Brake Duty Solenoid A6 No Connection
B7 2-4 Brake Duty Solenoid A7 Engine Speed Sensor
B8 High Clutch Duty Solenoid A8 No Connection
B9 Low Clutch Duty Solenoid A9 No Connection
B10 N Position Switch A10 Vehicle Speed Sensor Out (2W D Only)
B11 D Position Switch A11 3rd START Select Switch
B12 Low & Reverse Brake Oil Pressure Switch A12 4L Mode Switch (4W D Only)
B13 Vehicle Speed Sensor A13 No Connection
B14 ATF Thermo Sensor Ground A14 No Connection
B15 No Connection A15 No Connection
B16 No Connection A16 Accelerator Pedal Position Sensor
B17 Lock-up Duty Solenoid A17 3 Position Switch
B18 Vign (Ignition Power Supply) A18 DIAG Switch (Test Switch)
B19 R Position Switch A19 A/T OIL TEMP Indicator Lamp
B20 High Clutch Oil Pressure Switch A20 CHECK TRANS Indicator Lamp
B21 L Position Switch A21 POW ER DRIVE Indicator Lamp
B22 Ground (Shift Solenoid) A22 No Connection
B23 Line Pressure Solenoid A23 No Connection
B24 Vign (Ignition Power Supply) A24 POW ER DRIVE Select Switch
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A1-28 CONSTRUCTION AND FUNCTION
Item Description
Learning function The learning function is provided to correct the oil pressure control timing to engage or
disengage the clutch optimally in order to compensate changes of the engine performance
and changes of the transmission with time. It is controlled to bring the shift time closer to
the value pre-set to the TCM.
Fail-safe function In the case of a malfunction of the vehicle speed sensor, APP sensor, all solenoids or the
inhibitor switch, TCM automatically begins fail-safe control to minimize effects on driving.
The gear is fixed in 3rd gear and the power supply to the solenoid is shut off so that the
solenoid does not work. Lock up clutch is disengaged in this mode.
Self-diagnosis function Parts required for controlling the automatic transmission are provided with a self-diagnosis
function. W hen any trouble occurs, the check trans indicator lamp blinks to warn the driver.
The trouble code is memorized in the TCM.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
CONSTRUCTION AND FUNCTION 7A1-29
CONTROL ITEM, INPUT AND OUTPUT
Control item
Item
Line
pressure control
Gear shift
control
Shift
pattern
selection
Lock-up control Direct
electronic shift
control
(DECS)
Learning control
Fail-safe function
Self-
diagnosis function
Speed sensor
Turbine sensor
Engine speed sensor
Brake switch
Inhibitor switch
Mode select switch
4L switch (4W D Only)
ATF thermo sensor
High clutch oil pressure switch
2-4 brake oil pressure switch
Low & Reverse brake oil pressure
switch
Input
Accelerator Pedal position sensor
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & Reverse brake solenoid
Lock-up solenoid
Shift pattern indicator lamp
ATF temperature indicator lamp
Output
Check trans indicator lamp
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A1-34 CONSTRUCTION AND FUNCTION
MAJOR INPUT/OUTPUT COMPONENT AND THEIR FUNCTIONS
Speed sensor Detects output shaft revolution and sends rpm signal to TCM.
Turbine sensor Detects input shaft revolution and sends rpm signal to TCM.
Engine speed sensor Inputs engine revolution from engine control computer.
Brake switch Detects brake pedal operation by the driver and sends signal
to TCM.
Inhibitor switch Detects select lever position and sends signal to TCM.
Mode select switch Detects "Power Drive" or "3rd Start" selected by the driver and
sends signal to TCM.
4L switch (4W D Only) Inputs 4L mode from transfer control computer.
ATF thermo sensor Detects ATF temperature and sends signal to TCM.
High clutch oil pressure switch Detects high clutch supply oil pressure and sends signal to
TCM.
2-4 brake oil pressure switch Detects 2-4 brake supply oil pressure and sends signal to
TCM.
Low & Reverse brake oil pressure switch Detects low & reverse brake supply oil pressure and sends signal to TCM.
Accelerator Pedal position sensor Inputs throttle opening angle from engine control computer.
Input
TCM Judges necessary line pressure, gear shifting point and lock-up
operation based on electrical signals from switches and
sensors and sends appropriate signals to solenoids.
Line pressure solenoid Regulates oil pump delivery pressure to the appropriate line
pressure for current driving conditions based on a signal from
TCM.
Low clutch solenoid Selects appropriate gear shifting position for current driving
conditions and regulates low clutch supply oil pressure based
on a signal from TCM.
High clutch solenoid Selects appropriate gear shifting position for current driving
conditions and regulates high clutch supply oil pressure based
on a signal from TCM.
2-4 brake solenoid Selects appropriate gear shifting position for current driving
conditions and regulates 2-4 brake supply oil pressure based
on a signal from TCM.
Low & Reverse brake solenoid Selects appropriate gear shifting position for current driving
conditions and regulates low & reverse brake supply oil
pressure based on a signal from TCM.
Lock-up solenoid Regulates lock-up pressure to appropriate level for current
driving conditions based on a signal from TCM.
Mode indicator lamp Indicates POW ER DRIVE or 3rd START switch position.
Speed meter signal (2W D Only) Outputs vehicle speed to the speed meter.
A/T OIL TEMP indicator lamp Indicates A/T OIL TEMP indicator lamp in case of high
temperature.
Output
CHECK TRANS indicator lamp Indicates CHECK TRANS indicator lamp in case of
malfunction.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007