7A2-126 TRANSMISSION CONTROL SYSTEM (JR405E)
• Sticking of low & reverse brake solenoid valve
• Refer to symptom diagnosis No. A2: Vehicle Dose Not Run in R Range
6. If there is no parking. • Faulty parking pawl
• Refer to symptom diagnosis No. G1: Vehicle Moves in P Range or Parking Gear in Not
Disengaged other than P Range.
Notice: The check for the cause of abnormal noise and
vibration must be made with extreme care as it could
also be due to loss of balance in the propeller shaft,
differential, the torque converter, etc. Or insufficient
bending, rigidity, etc. in the powertrain.
Shift Speed Chart 1. All upshifts have a solid green line with:• 1-2 has black filled diamond plot points
• 2-3 has black filled squre plot points
• 2-4 has back filled circular plot posints
2. All donwshift have a sloid blue line with:
• 2-1 has white filled diamonf plot points
• 3-2 has white filled squre plot points
• 4-3 has white filled circular plot points
3. Torque converter clutch apply points have a dashed orange line with:
• 2nd apply has black filled diamond plot points
• 3rd apply has black filled squre plot points
• 4th apply has black filled circulat plot points
4. Torque converter clutch release points have a dashed pink line with:
• 2nd release has white filled diamond plot points
• 3rd release has white filled squre plot points
• 4th release has white filled circulat plot points
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-138 TRANSMISSION CONTROL SYSTEM (JR405E)
High clutch solenoid valve control signal• Measurement terminal: 8 of C-95 (+) & 22 of C-95 (-)
• Measurement scale: 5 volts/div & 10 ms/div
• Measurement condition: P or N range
Low clutch solenoid valve control signal
• Measurement terminal: 9 of C-95 (+) & 22 of C-95 (-)
• Measurement scale: 5 volts/div & 10 ms/div
• Measurement condition: D range with 4th gear Torque converter clutch (TCC) solenoid valve
control signal
• Measurement terminal: 17 of C-95 (+) & 5 of C-95 (-)
• Measurement scale: 10 volts/div & 5 ms/div
• Measurement condition: TCC is commanded OFF
Torque converter clutch (TCC) solenoid valve
control signal
• Measurement terminal: 17 of C-95 (+) & 5 of C-95 (-)
• Measurement scale: 10 volts/div & 5 ms/div
• Measurement condition: TCC is commanded ON
0V
0V
0V
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-143
Description and Operation
Transmission Identification Information
Legend1. Drive train type (UK020= 2WD/ UK021= 4WD)
2. Production calendar year (6=2006/ 7= 2007/ 8= 2008) 3. Production month (1 - 9= January - September/ X=
October/ Y= November/ Z= December)
4. Sequential number
Transmission General Description
Legend
1. Torque converter housing
2. Torque converter
3. High clutch
4. Reverse clutch
5. 2-4 brake
6. Low clutch
7. Low & reverse brake 8. Output shaft
9. Extension housing
10. Input shaft 11 . O i l p u m p
12. Valve body
13. Low one-way clutch
14. Parking gear
JATCO CORP
UK02
No. 6X80652 1
2 3 4
4WD
2WD
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
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.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-148 TRANSMISSION CONTROL SYSTEM (JR405E)
Valve Body Assembly
Legend1. Oil filter
2. Pressure control (PC) solenoid valve
3. Low & reverse brake solenoid valve
4. High clutch solenoid valve
5. Torque converter clutch (TCC) solenoid valve
6. 2-4 brake solenoid valve
7. Low clutch solenoid valve 8. Low & reverse brake transmission fluid pressure
(TFP) switch
9. High clutch TFP switch
10. 2-4 brake TFP switch
11. Transmission fluid temperature (TFT) sensor
12. Lower body
13. Upper body
Employing the direct electronic control (Direct
Electronic Shift Control: DESC) for the clutch pressure
has simplified the oil pressure circuit, reduced the
number of functional components and made the control
valve compact. The control valve body is divided into
the upper body and the lower body. All solenoid valves,
the transmission fluid pressure (TFP) switch and the
transmission fluid temperature (TFT) sensor are
installed to the lower body. Three-way valve type
solenoid valves providing high responsibility are
employed. The pressure control (PC) solenoid valve is
switched between ON and OFF, and other solenoid valves repeat ON and OFF at 50Hz (duty cycle). When
the solenoid valve is driven based on the signal from
the TCM, the fluid pressure is changed.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-149
Legend1. Pressure control (PC) solenoid valve
2. Low & reverse brake solenoid valve
3. High clutch solenoid valve
4. Torque converter clutch (TCC) solenoid valve
5. 2-4 brake solenoid valve
6. Low clutch solenoid valve
Pressure Control (PC) Solenoid Valve
The pressure control (PC) solenoid valve controls the
transmission fluid supply to the pressure regulator
spool valve in the valve body. The TCM controls the
solenoid valve by ON/ OFF signal based on the vehicle
running conditions. The TCM turns ON the solenoid
valve when a lower line pressure is required and turns
OFF when a higher line pressure is required. With the
operation of this solenoid valve, the operation and shift
of the hydraulic circuit in the transmission can be
performed smoothly. The PC solenoid valve is
controlled according to the range position, speed
sensor signals, transmission fluid temperature signal
and the accelerator pedal position signal. Shift Solenoid Valve
Legend
1. Output port
2. Supply port
3. Drain port
4. Deenergized (commanded OFF)
5. Energized (commanded ON)
All shift solenoid valve is a duty cycle type, which is
turned ON and OFF at 50 Hz. The ration of ON and
OFF time can be freely controlled within 0 to 100%.
While no power is supplied, the solenoid valve supplies
output pressure. The low clutch solenoid valve adjusts
the low clutch pressure, the high clutch solenoid valve
adjusts the high clutch pressure, the 2-4 brake solenoid
valve adjusts the 2-4 brake pressure, and the low &
reverse brake solenoid valve adjusts the low & reverse
brake pressure respectively.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-150 TRANSMISSION CONTROL SYSTEM (JR405E)
Torque Converter Clutch (TCC) Solenoid Valve
Legend1. Output port
2. Drain port
3. Supply port
4. Deenergized (commanded OFF)
5. Energized (commanded ON)
The torque converter clutch (TCC) solenoid valve is a
duty cycle type, which is turned ON and OFF at 50 Hz.
The ration of ON and OFF time can be freely controlled
within 5 to 95%. While no power is supplied, the
solenoid valve drains the output pressure.
Transmission Fluid Pressure (TFP) Switch
Legend 1. High clutch TFP switch
2. 2-4 brake TFP switch
3. Low & reverse brake TFP switch
Legend
1. Fluid pressure
2. Diaphram
3. Disc
4. Contact point
The transmission fluid pressure (TFP) switch detects
the condition of the fluid pressure supply to the clutch
and brake, and then sends the result to the TCM. The
TFP switch is turned ON when the fluid pressure
reaches the switch working pressure, and turned OFF
when the fluid pressure decreases below the specified
value. The high clutch TFP switch detects the high
clutch fluid pressure, the 2-4 brake TFP switch detects
the 2-4 brake fluid pressure, and the low & reverse
brake TFP switch detects the low & reverse brake fluid
pressure respectively.
Transmission Fluid Temperature (TFT) Sensor
Legend
1. TFT sensor
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007