2004 ISUZU TF SERIES lock

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.

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.

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.

CONSTRUCTION AND FUNCTION 7A1-45
4th Gear (O/D) in D Range
The driving force from the input shaft is transmitted to the rear sun gear and reverse & high clutch drum.
Since the 2-4 brake is engaged, the front sun gear is fixed. As a result, the front pinion gear rotates both
itself and together with other gears clockwise. This rotation increases the speed of rotation of the front
internal gear and is transmitted to the output shaft.

7A2-2 DIAGNOSIS (JR405E)
PAGE
DTC P0748 (FLASH CODE 35) LINE PRESSURE SOLENOID FAILURE.......................7A2-60
DTC P1860 (FLASH CODE 36) LOCK-UP DUTY SOLENOID FAILURE.........................7A2-62
DTC P1853 (FLASH CODE 26) LOW & REVERSE BRAKE PRESSURE
SWITCH FAILURE......................................................................................................................7A2-64
DTC P1858 (FLASH CODE 27) 2-4 BRAKE PRESSURE SWITCH FAILURE................7A2-68
DTC P1863 (FLASH CODE 28) HIGH CLUTCH PRESSURE SWITCH FAILURE..........7A2-72
DTC P0731 (FLASH CODE 41) 1st GEAR RATIO ERROR................................................7A2-76
DTC P0732 (FLASH CODE 42) 2nd GEAR RATIO ERROR...............................................7A2-76
DTC P0733 (FLASH CODE 43) 3rd GEAR RATIO ERROR................................................7A2-76
DTC P0734 (FLASH CODE 44) 4th GEAR RATIO ERROR................................................7A2-76
DTC P1750 (FLASH CODE 51) LOW & REVERSE BRAKE FAIL-SAFE
VALVE FAILURE........................................................................................................................7A2-78
DTC P1755 (FLASH CODE 52) 2-4 BRAKE FAIL-SAFE VALVE FAILURE....................7A2-80
DTC P0602 Programming Error ................................................................................... 7A2-82
SYMPTOM DIAGNOSIS.............................................................................................................7A2-83
SYMPTOM DIAGNOSIS TABLE...............................................................................................7A2-84
No. A1: VEHICLE DOES NOT RUN IN D, 3, 2, L and RANGE..........................................7A2-93
No. A2: VEHICLE DOES NOT RUN IN R RANGE................................................................7A2-94
No. A3: VEHICLE DOES NOT RUN IN D, 3, 2 and RANGE...............................................7A2-95
No. B1: VEHICLE RUNS IN N RANGE...................................................................................7A2-96
No. B2: POOR ACCELERATION AT STARTING.................................................................7A2-97
No. B3: ENGINE RACE UP DURING STARTING (SLIP)....................................................7A2-100
No. B4: LARGE SHOCK WHEN SHIFT LEVER IS CHANGED TO N TO D
RANGE OR N TO R RANGE....................................................................................................7A2-103
No. B5: ENGINE STALLS WHEN SELECTING FROM N RANGE TO R, D, 3, 2
OR L RANGE...............................................................................................................................7A2-104
No. B6: ENGINE STARTER DOES NOT RUN IN P OR N RANGE...................................7A2-106
No. B7: ENGINE STARTER RUNS EXCEPT IN P OR N RANGE.....................................7A2-106
No. B8: EXTENDED TIME LAG WHEN SHIFT LEVER IS CHANGED TO N TO D........7A2-106
No. B9: EXTENDED TIME LAG WHEN SHIFT LEVER IS CHANGED TO N TO R........7A2-106
No. B10: BRAKE IS APPLIED IN R RANGE..........................................................................7A2-107
No. B11: INSUFFICIENT STARTING OR SHAKING IN D RANGE...................................7A2-107