reverse ISUZU TF SERIES 2004 Workshop Manual

CONSTRUCTION AND FUNCTION 7A1-35
CONTROL CIRCUIT BLOCK DIAGRAM



Speed sensor
Turbine sensor
Brake switch
Inhibitor switch
Power drive, 3rd start
switch
ATF oil thermo sensor
High clutch oil pressure
switch
2-4 brake oil pressure
switch
Low & reverse brake oil
pressure switch
Transfer control module
(4WD Only)



Engine Control Module
(ECM)
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & reverse brake
solenoid
Lock-up solenoid
ATF temperature
indicator lamp
Speed meter (2WD
Only)
Power, 3rd start indicator
lamp
Check trans indicator
lamp
Data link connector Self-diagnosis
function



Transmission
Control
Module
(TCM)
4L mode
Engine
speed
Throttle
angle
Figure 54. Control Circuit Block Diagram

7A1-36 CONSTRUCTION AND FUNCTION
GEAR TRAIN (TRANSMISSION MECHANISM) OPERATION AND
HYDRAULIC CIRCUIT
CONSTRUCTION AND OPERATION
The JR405E consists of two sets of planetary gears, three multiple plate clutches, two multiple plate brakes
and one one-way clutch.





COMPONENT NAME AND FUNCTION
Component Name Symbol Function
Low Clutch L/C Connects the front planetary carrier to the rear
internal gear.
Engaged at 1st, 2nd and 3rd gear.
High Clutch H/C Connects the input shaft to the front planetary
carrier.
Engaged at 3rd and 4th (O/D) gear.
Reverse Clutch R/C Connects the input shaft to the front sun gear.
Engaged at Reverse gear.
Low & Reverse Brake L&R/B Locks the front planetary carrier.
Engaged at L range and Reverse gear.
2-4 Brake 2-4/B Locks the front sun gear.
Engaged at 2nd and 4th (O/D) gear.
Low One-way Clutch L/O.C Allows the front planetary carrier to turn forward
(clockwise) but locks to opposite direction
(counterclockwise).
Operative when accelerating.
Low Clutch Solenoid L/C.S Regulates low clutch pressure.
High Clutch Solenoid H/C.S Regulates high clutch pressure.
Low & Reverse Brake Solenoid L&R/B.S Regulates low & reverse brake pressure.
2-4 Brake Solenoid 2-4/B.S Regulates 2-4 brake pressure.
Lock-up Solenoid L/U.S Regulates lock-up clutch pressure.
High Clutch Oil Pressure SW H/C.P/SW Detects high clutch supply oil pressure.
Low & Reverse Brake Oil Pressure SW L&R/B.P/SWDetects low & reverse brake supply oil pressure.
2-4 Brake Oil Pressure SW 2-4/B.P/SWDetects 2-4 brake supply oil pressure.

CONSTRUCTION AND FUNCTION 7A1-37
COMPONENT AND THEIR OPERATING CONDITION

Clutch Brake Solenoid Pressure Switch
Select
lever
position
Gear
position
Gear
Shift
Lock-
up
L/C
H/C
R/C
L/O.C
L&R/B
2-4/B
L/C.S
H/C.S
L&R/
B.S
2-4/
B.S
L/U.S H/
C.P/
SWL&R/
B.P/
SW2-4
B.P/
SW
P - -

R Reverse -

N - -

1st

2nd
3rd


D
4th

1st

2nd
3rd


3
4th(*1)


1st

2nd

3rd(*1)



2
4th(*1)


1st
2nd(*1)

3rd(*1)



L
4th(*1)



*1:Transmission is shifted at high speed to prevent engine over-run.
- Engaged or operated
- Operative when accelerating

7A1-38 CONSTRUCTION AND FUNCTION
P Range
Though the driving force of the input shaft is transmitted to the rear sun gear and reverse & high clutch drum,
the driving force is not transmitted to the output shaft since all of the clutches and brakes are not engaged.
Therefore, the vehicle can move at this condition. However, since the output shaft is mechanically locked
with the parking pawl, the rear planetary carrier and front internal gear are locked. For this reason, the
vehicle does not move.

CONSTRUCTION AND FUNCTION 7A1-39
N Range
Though the driving force of the input shaft is transmitted to the rear sun gear and reverse & high clutch drum,
the driving force is not transmitted to the output shaft, since all of the clutches and brakes are not engaged.
Therefore, the vehicle can move at this condition.

7A1-40 CONSTRUCTION AND FUNCTION
Reverse Gear in Range
The driving force from the input shaft is transmitted to the rear sun gear and reverse & high clutch drum. In the R
range, the reverse clutch is engaged and the driving force is transmitted to the front sun gear and rotates it
clockwise. The low & reverse brake is also engaged and the front planetary carrier is fixed so that the front pinion
gear does not rotate clockwise but can rotate counterclockwise. As a result, the output shaft rotates
counterclockwise and the vehicle goes back.

CONSTRUCTION AND FUNCTION 7A1-41
1st Gear in D, 3, 2 Range
The driving force from the input shaft is transmitted to the rear sun gear and reverse & high clutch drum.
Since the low clutch is engaged, the movement of the rear internal gear is restricted and, since the low one-
way clutch acts at the same time, counterclockwise rotations of the rear internal gear are locked. As a result,
the driving force transmitted to the rear sun gear rotates the rear planetary carrier clockwise, is decreased in
speed and transmitted to the output shaft.
When decelerating, since the rotating speed of the rear planetary carrier (rear pinion gear) is higher than that
of the rear sun gear and therefore, the rear internal gear attempts to rotate clockwise. At this time, the low
one-way clutch does not act but races and therefore the rear internal gear rotates clockwise. That is, the
reverse torque from the driving shaft is not transmitted to the engine side and therefore, the engine brake
does not act.

7A1-42 CONSTRUCTION AND FUNCTION
1st Gear in L Range
The basic mechanism is the same as in the D, 3, and 2 Range. To apply the engine brake, the low & reverse
brake is engaged to restrict the movement of the low one-way clutch.
When decelerating, since the rear internal gear is fixed, reverse torque from the drive shaft is transmitted to
the engine side so that the engine brake is applied.

CONSTRUCTION AND FUNCTION 7A1-43
2nd Gear in D, 3, 2 Range
The driving force from the input shaft is transmitted to the rear sun gear and reverse & high clutch drum. As
in the case of the 1st gear, since the low clutch is engaged, the movement of the rear internal gear is
restricted. Since the 2-4 brake is engaged, the front sun gear is fixed. As a result, movement of the rear
internal gear is restricted, and the driving force transmitted to the rear sun gear rotates the rear planetary
carrier clockwise, and is decreased and output. The rotating speed of the rear planetary carrier is increased
as the rear internal gear rotates.
When decelerating, the engine brake is applied.

7A1-44 CONSTRUCTION AND FUNCTION
3rd Gear in D, 3 Range
The driving force from the input shaft is transmitted to the rear sun gear and reverse & high clutch drum. As
in the case of the 1st gear and 2nd gear, since the low clutch is engaged, the movement of the rear internal
gear is restricted. Since the high clutch is engaged, the driving force from the input shaft is directly
transmitted to the rear internal gear. As a result, the rpm of the rear sun gear and the rear internal gear
becomes the same as that of the input shaft so that the rear pinion gear rotates not independently but
together with the rear sun gear and rear internal gear.
When decelerating, the engine brake is applied.