2004 ISUZU TF SERIES engine oil

7A1-6 CONSTRUCTION AND FUNCTION
ELECTRONIC CONTROL COMPONENTS LOCATION

4WD Only 4WD 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
Select lever








Power Drive
, 3rd Start select 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
Throttle Position Sensor


Engine Control Module (ECM)
Data link connector

7A1-8 CONSTRUCTION AND FUNCTION
STRUCTURE AND FUNCTION OF COMPONENT
TORQUE CONVERTER (WITH LOCK-UP FUNCTION)

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 is disengaged and by means of a lock-up piston when it is engaged.

The torque converter is of the symmetrical, three-element, single-stage, two-phase type.

As shown in the drawing, the symmetrical three-elements refer to three elements (components) consisting
of impeller (1), turbine (2) and stator (3) that are arranged symmetrically (figure 5).

"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.


















1. Pump Impeller
2. Turbine Runner
3. Stator














1. Pump Impeller
2. Turbine Runner
3. Stator
4. Converter Cover
5. One-way Clutch
6. Lock-up Piston
7. Torsion Damper

Figure 5. Torque Converter
Figure 6. Construction of Torque Converter

Lock-up mechanism

"Lock-up" refers to a fixed state of the lock-up piston inside the torque converter and thus connects the
engine directly to the transmission.

The hydraulic pressure for the lock-up control is supplied from two circuits.

When the lock-up is disengaged (Figure 7)

When the lock-up is disengaged, the torque converter operating pressure is supplied from the oil passage
(A) to between the cover and the lock-up piston, and separates the lock-up piston clutch facing and
converter cover.

As a result, the engine drive power is transmitted from the converter cover to the pump impeller, the ATF
and to the turbine. The torque converter function as a fluid connector in this condition.

The torque converter operating pressure is supplied from the oil passage (A), passes through the oil
passage (B).

When the lock-up is engaged (Figure 8)

When the lock-up is engaged, the torque converter operating pressure is supplied from oil passage (B) to
the oil pump impeller, turbine, then to the stator side. The oil between the lock-up piston and converter
cover is drained.

Since the force acting on the right side of the lock-up piston is greater than force on the left side, it
connects the lock-up piston clutch facing with the converter cover, thereby increasing the transmission
efficiency.

CONSTRUCTION AND FUNCTION 7A1-9


Figure 7. Lock-up Control (Disengaged) Figure 8. Lock-up Control (Engaged)
OIL PUMP

The oil pump generating oil pressure is a small-size 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. Sine the inner rotor in the oil pump is fitted with the
drive sleeve of the torque converter, it works by the power from the engine.

Figure 9. Construction of Oil Pump Figure 10. Location of Oil Pump

When the inner rotor in the oil pump rotates, ATF is sucked in from the oil pan, passed between the inner
rotor, outer rotor and crescent and discharged. This pressure discharged is sent to the pressure
regulator valve in the control valve and adjusted as required for operating the A/T. The flow rate under
pressure increases or decreases in proportion of the number of rotations.


Figure 11. Operation of Oil Pump

7A1-10 CONSTRUCTION AND FUNCTION
INPUT SHAFT

The input shaft has some oil holes, through which lubricating ATF is supplied to the torque converter,
bearings, etc.

The input shaft is fitted the turbine runner in the torque converter, reverse & high clutch drum and 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 ATF is supplied to the bearings,
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.

GEAR SHIFTING MECHANISM

The JR405E consists of two sets of planetary gears, three multiple plate clutches, two multiple plate
brakes and a one-way clutch. They are activated in different combinations in any of four forward and one
reverse gear positions.

Principle of gear shifting (Figure 12)

Planetary gears have the advantage of a compact configuration because of the way they are constructed
with a single central shaft.

Also, unlike the manual transmission gears that require changing of gear mesh, the gear ratio of the
planetary gears can be changed more easily by locking, releasing or rotating only some of their parts.

A planetary gear is made up of a sun gear (1) at its center and pinion gears (2) each of which rotates
about its own center and also along the sun gear, as shown. They are all called in the internal gear (3).

Also, since the pinion gears are further supported by the planetary carrier (4), they rotate as a unit in the
same direction and at the same rate.

As shown above, each planetary gears are constructed of three elements; a sun gear, pinion gears, and
internal gear and a planetary carrier. Gear shifting is achieved by conditioning two of the three elements
namely the sun gear, internal gear and the planetary carrier.

The planetary gears are locked by the clutch, brake and one-way clutch according to the gear shifting.
















1. Sun Gear
2. Pinion Gear
3. Internal Gear
4. Planetary Carrier

Figure 12. Planetary Gear

CONSTRUCTION AND FUNCTION 7A1-25
TRANSMISSION CONTROL MODULE (TCM)

The TCM is fitted side of brake pedal by means of two stud bolts.

The 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.















        




















 
 
 
 
 
 
 












      
  

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 Range Switch A2 P Range 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 Range Switch A10 Vehicle Speed Sensor Out (2WD Only)
B11 D Range Switch A11 3rd START Select Switch
B12 Low & Reverse Brake Oil Pressure Switch A12 4L Mode Switch (4WD Only)
B13 Vehicle Speed Sensor A13 No Connection
B14 ATF Thermo Sensor Ground A14 No Connection
B15 Ground A15 No Connection
B16 No Connection A16 Throttle Position Sensor
B17 Lock-up Duty Solenoid A17 3 Range Switch
B18 Vign
Ignition Power Supply) A18 DIAG Switch (Test Switch)
B19 R Range Switch A19 A/T OIL TEMP Indicator Lamp
B20 High Clutch Oil Pressure Switch A20 CHECK TRANS Indicator Lamp
B21 L Range Switch A21 POWER DRIVE Indicator Lamp
B22 Ground (Shift Solenoid) A22 No Connection
B23 Line Pressure Solenoid A23 No Connection
B24 Vign (Ignition Power Supply) A24 POWER DRIVE Select Switch

7A1-26 CONSTRUCTION AND FUNCTION
CONTROL MECHANISM
CONTENT OF FUNCTION AND CONTROL
Item Description
Line pressure control TCM issues a signal according to the vehicle traveling, engine load and other conditions to
TCM and the ON/OFF type line pressure solenoid is driven to switch the line pressure to
high or low pressure.
The line pressure solenoid is switched to the low pressure side when the solenoid is turned
ON (power supplied) and to the high pressure side when turned OFF (no power supplied).
In the forward travel range (D, 3, 2, L range), the line pressure decreases lower than that in
the P, N, and R range through the oil pressure circuit for the forward travel range.


Gear shift control The TCM issues a shift solenoid drive signal based on the traveling mode switch, inhibitor
switch, vehicle speed, throttle opening and other input signal to control the optimum gear
position automatically.
Speed change features have been set up to the TCM; the normal mode is suited to usual
traveling and the power mode is appropriate when the vehicle is loaded or accelerates the
speed.
In addition, speed change features used only for high oil temperature, hill climbing, and
down have been set up to the TCM, which are automatically switched depending on the
traveling conditions.
When the oil temperature is low (below 10
C), speed change from the third to the fourth
speed is prohibited by the gear shift control.


Shift pattern selection
control
According to a vehicle condition, the TCM selects the following shift pattern.

Selection Priority Shift Pattern 3rd Start Lamp Power Drive Lamp
High High Temperature OFF OFF
3rd Start ON
4L
Power SW Off
OFF
Down Slop Power SW On
Power ON
Up Slope
Low Normal
OFF
OFF

- High temperature mode -
High temperature mode setting condition
ATF temperature: More than 123
C
Above condition is met for more than 10 seconds.
High temperature mode cancel condition
ATF temperature: Less than 116
C
Above condition is met for more than 10 seconds.

- 3rd start mode -
3rd start mode setting condition
3rd start switch: On  Off (Pushed)
Vehicle speed: Less than 11km/h
ATF temperature: Less than 115
C
Throttle position: Less than 8%
Select lever position: D range
Above conditions are met at the same time.
3rd start mode reset condition
3rd start switch: On  Off again(Pushed again)
Vehicle speed: More than 34km/h
Select lever position: Other than D range
At least, one of above conditions is met.

CONSTRUCTION AND FUNCTION 7A1-27
Item Description
- 4L mode -
4L mode setting condition
4L switch: On
Vehicle speed: More than 5km/h
Above conditions are met at the same time.
4L mode reset condition
4L switch: Off
Vehicle speed: Less than 4km/h
Above conditions are met at the same time.

- Down slope mode -
Down slope mode setting condition
Brake switch: On
Engine idle condition: More than 2.5 seconds
Select lever position: D or 3 range
Vehicle speed: More than 55km/h
Vehicle speed change: More than 1km/h
Above conditions are met at the same time.
Down slope mode reset condition
Engine idle condition: Not idle condition
Select lever position: Other than D or 3 range
At least, one of above conditions is met.

- Power Mode -
When power drive switch is On at only D range or 3 range, the shift change is performed by
1 – 4 speed based on shift diagram set as power pattern.

- Up slope mode -
Up-slope reasoning value is calculated from the average throttle angle and the average
acceleration. Otherwise, up-slope reasoning value is calculated from the vehicle speed.
TCM judges as up-slope mode when the former is bigger than latter.


Lock-up control The lock-up solenoid adjusts the pressure based on the signal from the TCM according to
the vehicle speed, throttle opening and other input signals based on the pre-set lock-up
point to control the lock-up.
Smooth lock-up control engages and disengages the clutch smoothly at the time of lock-up.
When the oil temperature is low (below 20
C) or high (above 128
C), lock-up is prohibited
even when the vehicle is at a lock-up speed.
The lock-up is disengaged also when the throttle is closed.
Direct electronic shift
control (DESC)
The duty cycle type solenoid is used for each clutch and brake. The solenoid adjusts the
clutch pressure to be suited to the engine load and vehicle traveling condition based on the
signal from the TCM. The pressure switch provided in the control valve oil passage sends
the oil pressure condition to the TCM to control the disengagement and engagement of the
clutch and brake directly and finely.
Learning control Learning is controlled 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 speed-change time closer to the
value pre-set to the TCM.

CONSTRUCTION AND FUNCTION 7A1-29
CONTROL ITEM, INPUT AND OUTPUT

Control item


Item

Line
pressure
control
Gear
shift
control
Shift
pattern
selection
Lock-up
controlDirect
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 (4WD Only)

ATF thermo sensor
High clutch oil pressure switch

2-4 brake oil pressure switch

Low & Reverse brake oil pressure
switch
Input
Throttle 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