piston ISUZU TF SERIES 2004 Workshop Manual
[x] Cancel search | Manufacturer: ISUZU, Model Year: 2004, Model line: TF SERIES, Model: ISUZU TF SERIES 2004Pages: 4264, PDF Size: 72.63 MB
Page 3957 of 4264
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 front planetary gear is fixed to the drive plates of 2-4 brake and reverse clutch.
The planetary carrier of front planetary gear is fixed to the drum of low clutch, the drive plates of low &
reverse brake and the hub of high clutch.
The internal gear of front planetary gear and the planetary carrier of rear planetary gear are connected as
one, and they are fixed to output shaft.
The sun gear of rear planetary gear is fixed to input shaft.
The internal gear of rear planetary gear is fixed to the hub of 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 in the fluid 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 the figure A by 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 or disengaged. 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 for the purpose of preventing
the clutch drag due to oil pressure generated by residual ATF because of the centrifugal force while the
clutch is racing (under no oil pressure).
For the low clutch and high clutch, a centrifugal balance chamber always full of ATF is provided to offset
the excessive oil pressure, for the purpose of preventing the clutch drag due to oil pressure generated by
residual ATF because of the centrifugal force while the clutch is racing (under no oil pressure).
The solenoid in the control valve is driven based on the speed change signal from TCM and moves the
shift valve, thereby engaging the drive plate and driven plate through the piston of each clutch.
Resultantly, elements of the planetary gear unit are combined.
When the oil pressure is removed, the piston returns to the original position by the force of the return
spring.
Page 3959 of 4264
CONSTRUCTION AND FUNCTION 7A1-13
2-4 Brake and Low & Reverse Brake (Multi-Plate Brake)
The multi-plate brake is composed of drive plates and driven plates. By applying the oil pressure onto
the end surface of the plates, the clutch is engaged or disengaged. The oil pressure is adjusted with the
control valve according to the signal from the TCM.
All brakes use dish plates to prevent uncontrolled operation of the clutches when engaged, causing a
shock.
The solenoid in the control valve is driven based on the speed change signal from TCM and moves the
shift valve, thereby engaging the drive plate and driven plate through the piston of each clutch.
Resultantly, rotation of each element of the planetary gear unit is fixed.
When the oil pressure is removed, the piston returns to the original position by the force of the return
spring.
Figure 19. Construction of 2-4 Brake
Figure 20. Construction of Low & Reverse Brake
Low One-way Clutch
The low one-way clutch employs the sprag which locks the counterclockwise rotation of the front planetary
carrier and rear internal gear.
The one-way clutch outer race is fitted with the low clutch drum and the inner race with the transmission
case.
The outer race rotates freely clockwise but, when it attempts to rotate counterclockwise, the sprag
functions to lock the outer race.
When the vehicle is traveling in 1st gear in the D, 3 or 2range, the low one-way clutch locks the rear
internal gear via the low clutch. It is left free in the 2nd, 3rd or 4th gear position.
Figure 21. Construction of Low One-way Clutch
Page 3976 of 4264
7A1-30 CONSTRUCTION AND FUNCTION
LINE PRESSURE CONTROL
Either the throttle opening, vehicle speed, turbine rotational speed, ATF temperature or speed-change
range signal appropriate under the situation is issued from the TCM. The ON/OFF type line pressure
solenoid is actuated and switches the line pressure to high or low pressure.
The line pressure generated by the oil pump acts on the point A of the pressure regulator valve. When
the pressure control solenoid is turned ON by the signal from the TCM, the solenoid pressure does not
act. The line pressure is adjusted to match the spring force acting on the right side of the pressure
regulator valve.
When the pressure control solenoid is turned OFF, the solenoid pressure acts so that the line pressure is
adjusted to match the spring force acting on the right side of the pressure regulator valve.
As a result, the line pressure is adjusted to be low when the pressure control solenoid is ON and to be
high when the pressure control solenoid is OFF.
In the D, 3, 2 and L range, the line pressure through the oil pressure circuit acts onto the point B of the
pressure regulator valve and the pressure regulator valve moves so as to increase the pressure to be
drained, so that the line pressure is adjusted to be lower than the P, N, and R range by the difference of
area at the point B.
Figure 50. Line Pressure Control
LOCK-UP CONTROL
The lock-up solenoid adjusts the pressure and controls the lock-up based on the pre-set lock-up point,
according to the vehicle speed, throttle opening, engine rotations, turbine rotations and ATF temperature
input signal, based on the signal from the TCM.
Smooth lock-up control is employed to engage or disengage the clutch smoothly at the time of lock-up.
When the oil temperature is low (below 20C) or high (over 128C), lock-up is disengaged even though
the vehicle is at the lock-up speed.
The lock-up is disengaged also when the throttle is closed.
When the TCM determines the lock-up engagement, the DUTY ratio to supply power to the lock-up
solenoid is gradually increased (5% to 95%) and the oil between the lock-up piston and converter cover is
gradually drained.
As a result, the lock-up piston is fitted slowly under pressure to the converter cover securing smooth lock-
up engagement.
Page 4096 of 4264
7A2-104 DIAGNOSIS (JR405E)
No. B5: Engine Stalls When Selecting From N Range to
R, D, 3, 2 or L Range
Description:
The engine stalls when selecting from N or P range to a run range during the engine idling.
Diagnosis Hints:
As causes attributable to the engine, faulty idle up, insufficient engine output, etc. are considered.
As a cause of the AT system, faulty lockup piston system (lockup engine stall) is considered.
If the oil through resistance increases remarkably due to clogged oil cooler or some other reason, or if the ATF
level decreases, the lock-up piston works causing the engine stall.
Possible Cause:
Disordered idling speed, faulty idle up, faulty engine output, shortage output.
Insufficient ATF quantity (dropped level).
Clogged oil cooler (foreign substance mixed in).
Faulty lock-up piston (clogged oil passage of solenoid drive circuit, faulty operation).
Step Action Yes No
1 Gear ratio trouble diagnosis.
Travel in the following sequence for about 7 seconds or more in
each range: Start in the L range (1st) to 2 range (2nd) to 3 range
(3rd) to D range (4th) (to detect the gear ratio trouble exactly, this
process should be carried out)
Go to Step 2 Go to Step 2
2 Are any DTCs stored?
Go to DTC Chart Go to Step 3
3 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.
Go to Step 4
If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.
Overhaul the AT
unit.
4 Check of engine idle up speed
Does the idle speed increase when the air conditioning or other
electric load is turned on?
Go to Step 5
Repair the defect or
replace.
Page 4097 of 4264
DIAGNOSIS (JR405E) 7A2-105
Step Action Yes No
5 Inspection of electrical or mechanical fault
When the D range is selected from D at idling speed, is the signal
to the lock-up solenoid turned off using the Tech 2 or circuit
tester?
Control Valve
TCM
B17
B23 BLK Lock-up Solenoid
Te rm i n a l
Assembly
VIO Line Pressure Solenoid
E54
(4)
(6)H23
(14)
(6)C95
(17)
(23) BLK
VIO
TCM terminal
Lock-upB17
At lock-up Approx. 2.2 - 9.0 V (AC range)
At unlock-up Approx. 1.0 - 2.0 V (AC range)
Go to Step 6
Find a cause to turn
on the lockup
solenoid
6 Check of clogging of oil cooler
When blowing the oil cooler outlet with air, does some foreign
substance come out?
Clean or replace the
oil cooler.
Go to Step 7
Clogged lock-up
solenoid oil
passage. Faulty
operation of lock-up
piston.
Faulty control valve.
7 Is the stall revolution correct in D, 3, 2 and L range? Refer the
STALL TEST section in this manual.
Go to Step 8
Repair the defect or
replace.
8 Is the line pressure correct? Refer the LINE PRESSURE TEST
section in this manual.
Trouble in the AT
assembly or control
valve.
Repair the defect or
replace.
Page 4106 of 4264
7A2-114 DIAGNOSIS (JR405E)
No. C12: Large Shock When Gear is Shifted to 1st to 2nd or 2nd
to 1st
No. C13: Large Shock When Gear is Shifted to 2nd to 3rd or 3rd to
2nd
No. C14: Large Shock When Gear is Shifted to 3rd to 4th or 4th to
3rd
No. C15: Large Shock When Kick-down
No. C16: Large Shock When No Acceleration
No. C17: Large Shock When Gear is Shifted Down to 2nd to 1st in
L Range
No. C18: Large Shock (Other)
No. C19: Large Shock When Vehicle Speed is Downed by No
Accelerator Pedal or Vehicle is Stopped
Description:
Large shock is felt when the accelerator pedal is stepped on for acceleration and the gear is shifted up or down.
Large shock is felt when the accelerator pedal is stepped on for kick-down.
Large shock is felt when the accelerator pedal is not stepped on.
Large shock is felt when the shift lever is selected in L range.
Diagnosis Hints:
Basically same causes as "No. C1 - C8: Engine races up (slip)" are considered.
No. C20: Large lock-up shock
Description:
Large shock is felt at lock-up.
Diagnosis Hints:
Out of properties of input sensor or faulty lock-up piston pressure system are considered.
Trouble diagnosis flow is basically the same as "No. I1: No lock-up".
No. C21: Shift Down or Engine Over-run When The Accelerator
Pedal is Stepped on in 4th Gear
Description:
Shift down or engine over-run above the kick-down area.
Diagnosis Hints:
Basically same causes as "No. C1 - C8: Engine races up (slip)" are considered.
Page 4125 of 4264
DIAGNOSIS (JR405E) 7A2-133
No. G4: Large Noise During Idling with the Vehicle in Stop State
Description:
The transmission is noisy during the idling speed in all ranges.
Diagnosis Hints:
Causes such as solenoid operating sound or faulty oil pump are considered.
Distinguishing to some extent is possible by stopping the solenoid operation temporarily, checking the correlation
for the former case and, changing the line pressure and confirming the correlation with noise.
As a matter of course, noise may be generated around the engine, for instance, other than the AT and should be
checked carefully.
Note:
When the noise is generated only at the time of gear shift, it may be the sound of flowing ATF or gear
noise. If the sound varies depending on the gear speed to be shifted, it may be the gear noise generated
from the planetary gear and its related components. If the sound varies depending on the vehicle
speed, it may be the gear noise of the output system, and if varying depending on the engine speed, it
may be the gear noise of the input system or faulty torque converter.
In either case, sound may be "noise" depending on the origin and resonance object. When the object
generating the sound (resonance object) and the sound source (vibration source) are different,
investigation of the cause may be difficult.
No. H1: Judder Occurs at the Lock-up
Diagnosis Hints:
The vehicle body judders at lock-up.
Diagnosis Hints:
Slip due to burning of the lockup piston or insufficient fastening due to dropped working pressure are considered.
Trouble diagnosis flow is basically the same as "No. I1: No lock-up".
Note:
When the lock-up piston has burnt, foreign material mixed in the oil cooler is considered. In such a
case, inspect the oil cooler circuit for clogging of the oil cooler.
No. H2: Large Lock-up Shock
No. H3: Lock-up Point is High or Low
Description:
Large shock is felt at lock-up.
Lock-up point is excessive high or low.
Diagnosis Hints:
Out of properties of input sensor or faulty lock-up piston pressure system are considered.
Trouble diagnosis flow is basically the same as "No. I1: No lock-up".
Page 4126 of 4264
7A2-134 DIAGNOSIS (JR405E)
No. I1: No Lock-up
Description:
Lockup is not performed in spite of the lock-up area.
Diagnosis:
Lockup is not performed in spite of the lock-up area.
Monitor the signal to the lock-up solenoid while carrying out a running test.
When the output signal to the lock-up solenoid is correctly sent causing no lock-up, clogged lock-up solenoid oil
passage or malfunction of the lock-up piston may be considered.
Even the lock-up area, the output signal to the lock-up solenoid is not sent, fault of the ATF thermo sensor
controlling the lockup is considered. (Lock-up is not operated at ATF temperature less than 11C or more than
128C.)
Note:
When the lock-up piston has burnt, foreign material mixed in the oil cooler is considered. In such a
case, inspect the oil cooler circuit for clogging of the oil cooler
Possible Cause:
ATF thermo sensor detects low oil temperature (Lock-up is prohibited temperature less than 10C.).
Clogged oil passage of lock-up duty solenoid.
Trouble in control valve body (faulty operation, sticking, clogged oil passage).
Step Action Yes No
1 Are any DTCs stored?
Go to DTC Chart Go to Step 2
2 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.
Go to Step 3
If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.
Overhaul the AT
unit.
Page 4127 of 4264
DIAGNOSIS (JR405E) 7A2-135
Step Action Yes No
3 Inspection of electrical or mechanical fault
When the ATF oil temperature is above 20C and the vehicle
speed is 80km/h, is ON signal issued to the lock-up solenoid
using the Tech 2 or circuit tester?
Control Valve
TCM
B17
B23 BLK Lock-up Solenoid
Terminal
Assembly
VIO Line Pressure Solenoid
E54
(4)
(6)H23
(14)
(6)C95
(17)
(23) BLK
VIO
TCM terminal
Lock-upB17
At lock-up Approx. 2.2 - 9.0V (AC range)
At unlock-up Approx. 1.0 – 2.0V (AC range)
Clogged oil
passage of lock-up
solenoid or faulty
operation of lock-
up piston. Go to Step 4
4 Inspection of ATF oil thermo sensor.
Is the ATF oil temperature sensor terminal voltage correct?
After running using the Tech 2 data display function, is the ATF
temperature higher than 10C?
AT F
Te m p .
SensorTCM
B4 (+)
B14 (-)
H23
(8)
(3)C95
(4)
(1 4) BLU Te r m in a l
Assembly
BLU/BLKE54
(2)
(8) BLU
BLU/BLK
TCM terminal
Temperature (deg. C)
B4 (Output voltage)
201.55
401.08
600.7
800.5
1000.3
1200.2
Monitor the electric
system input
sensor signal and
find a signal
causing no lockup.
Repair the defect or
replace.
Page 4128 of 4264
7A2-136 DIAGNOSIS (JR405E)
No. J1: Oil Leaks from Breather
Description:
Oil leaks from breather.
Possible Cause:
ATF quantity is excessively.
No. J2: Oil Leaks Between Engine and Converter Housing
No. J3: Oil Leaks Between Main Case and Converter Housing
No. J4: Oil Leaks Between Main Case and Rear Housing
No. J5: Oil Leaks from Oil Pan
No. J6: Oil Leaks from Manual Shaft Oil Seal
No. J7: Oil Leaks from Oil Cooler Pipe Joint
Description:
Oil leaks between engine and converter housing.
Oil leaks between converter housing and main case.
Oil leaks between main case and rear housing.
Oil leaks from oil pan.
Oil leaks from manual shaft oil seal.
Oil leaks from oil cooler pipe joint.
Possible Cause:
Faulty oil seal or sealing of contact surface is considered.
No. Z1: Transmission Overheat
Description:
You smell the transmission burning.
The transmission smokes.
Possible Cause:
Slip of clutch.
If slip of clutch is caused, a DTC (gear ratio error) is stored.
Clogged oil cooler (foreign substance mixed)
ATF stirred excessively (too much ATF).
Faulty torque converter operating pressure.
Faulty lock-up piston.