2007 ISUZU KB P190 engine

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-159
Based on each transmission fluid pressure (TFP)
switch signal and each speed sensor signal and the
accelerator pedal angle, the duty cycle type shift
solenoid valve adjusts the clutch pressure to match the
engine load and vehicle running conditions. Controlling
the engagement and disengagement of the clutch and
brake pressure is directly and accurately controlled via
TCM, which is different to the conventional accumulator
type. Instead of the conventional system (On/ Off type
shift solenoid valve and shift valve), the combination of
the duty cycle type solenoid valve and the amplifier
(AMP) valve are used to adjust the clutch pressure to
match the engine load and vehicle driving conditions,
based on the signal from the TCM. Also, the TFP
switch provided in the fluid passage of the control valve
transmits to TCM, enabling the engagement and
disengagement control of the clutch and brake to be
directly and finely. When the gear is shifted from the
2nd to 3rd, 3rd to 4th, 4th to 3rd and 3rd to 2nd, the
clutch pressures on the engagement side and
disengagement side are simultaneously controlled. As
a result, engine racing or clutch drag is prevented
which enables a smooth and quick shift response.
Learning Control
Solenoid valve outputs
Low & reverse brake solenoid valve
2-4 brake solenoid valve
High clutch solenoid valve
Low clutch solenoid valve
TCM
Sensor inputs Input shaft speed (ISS) sensor
Output shaft speed (OSS) sensor
Transmission fluid temperature (TFT) sensor
Accelerator pedal position signal (via ECM)
Engine speed signal (via ECM)
Switch inputs
Low & reverse brake transmission fluid
pressure (TFP) switch
2-4 brake transmission fluid pressure (TFP)
switch
High clutch transmission fluid pressure (TFP)
switch

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ISUZU KB P190 2007

7A2-160 TRANSMISSION CONTROL SYSTEM (JR405E)
Legend1. Input shaft speed
2. Transmission fluid pressure
3. Time
4. Clutch engagement fluid pressure 5. Engine speed
6. Disengagement side clutch fluid pressure
7. Engagement side clutch fluid pressure
Transmission fluid pressure control timing is optimally
corrected at the time of clutch engagement and
disengagement. It is controlled to bring the shift time to
the value preset to the TCM, and compensate for the
changes in engine performance and transmission
characteristics. When the gear is shifted, the clutch
pressure (B) is optimally corrected so that the shift time
(A) is as close to the target value preset to the TCM.
The variation in the engine performance and changes
to transmission characteristics which occur with time,
can be compensated for based on the past shift results.
When the clutch is operated to shift the gear, the time
of the clutch fluid pressure release (D) on the
disengagement side is optimally corrected so that the
change of the engine speed (C) is optimum.
Notice: When the battery terminal is disconnected, the
contents of learning are cleared and as a result the shift
shock may increase. After the vehicle has traveled,
learning is repeated and the shock decreases
gradually.

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-165
First Gear In D, 3, 2 Range
Legend1. Input shaft
2. Front planetary carrier
3. Front pinion gear
4. Front sun gear
5. Rear sun gear
6. Rear pinion gear
7. Rear internal gear
8. Output shaft
9. Reverse clutch 10. 2-4 brake
11. High clutch
12. Front internal gear
13. Rear planetary carrier
14. Low clutch
15. Low & reverse brake
16. Low one-way clutch
17. Parking pawl
The driving force from the input shaft (1) is transmitted
to the rear sun gear (5) and reverse & high clutch drum.
As the low clutch (14) is engaged, the movement of the
rear internal gear (7) is restricted. Since the low one-
way clutch (16) acts at the same time,
counterclockwise rotations of the rear internal gear (7)
are locked. As a result, the driving force transmitted to
the rear sun gear (5) rotates the rear planetary carrier
(13) clockwise, then the rotation speed is decreased
and multiple forces is transmitted to the output shaft (8). When decelerating, the rotating speed of the rear
planetary carrier (13) (rear pinion gear [6]) is higher
than that of the rear sun gear (5) and the rear internal
gear (7) attempts to rotate clockwise. At this time, the
low one-way clutch (16) does not act but races, and
therefore the rear internal gear (7) rotates clockwise.
The reverse torque from the driving shaft is not
transmitted to the engine side and the engine brake
does not act.

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ISUZU KB P190 2007

7A2-166 TRANSMISSION CONTROL SYSTEM (JR405E)
First Gear In L Range
Legend1. Input shaft
2. Front planetary carrier
3. Front pinion gear
4. Front sun gear
5. Rear sun gear
6. Rear pinion gear
7. Rear internal gear
8. Output shaft
9. Reverse clutch 10. 2-4 brake
11 . H i g h c l u t c h
12. Front internal gear
13. Rear planetary carrier
14. Low clutch
15. Low & reverse brake
16. Low one-way clutch
17. Parking pawl
The basic mechanism is the same as in the D, 3, and 2
ranges. To apply the engine brake, the low & reverse
brake (15) is engaged to restrict the movement of the
low one-way clutch (16).
When decelerating, as the rear internal gear (7) is
fixed, reverse torque from the propeller shaft is
transmitted to the engine side so that the engine brake
is applied.

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-167
Second Gear
Legend1. Input shaft
2. Front planetary carrier
3. Front pinion gear
4. Front sun gear
5. Rear sun gear
6. Rear pinion gear
7. Rear internal gear
8. Output shaft
9. Reverse clutch 10. 2-4 brake
11. High clutch
12. Front internal gear
13. Rear planetary carrier
14. Low clutch
15. Low & reverse brake
16. Low one-way clutch
17. Parking pawl
The driving force from the input shaft (1) is transmitted
to the rear sun gear (5) and reverse & high clutch drum.
As in the case of the 1st gear, the low clutch (14) is
engaged and the movement of the rear internal gear (7)
is restricted. Since the 2-4 brake is engaged (10), the
front sun gear (4) is fixed. As a result, movement of the
rear internal gear (7) is restricted, and the driving force
transmitted to the rear sun gear (5) rotates the rear
planetary carrier (13) clockwise. The rotating speed of
the rear planetary carrier (13) is higher than in 1st gear as the rear internal gear (7) rotates. When decelerating,
the engine brake is applied.

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ISUZU KB P190 2007

7A2-168 TRANSMISSION CONTROL SYSTEM (JR405E)
Third Gear
Legend1. Input shaft
2. Front planetary carrier
3. Front pinion gear
4. Front sun gear
5. Rear sun gear
6. Rear pinion gear
7. Rear internal gear
8. Output shaft
9. Reverse clutch 10. 2-4 brake
11 . H i g h c l u t c h
12. Front internal gear
13. Rear planetary carrier
14. Low clutch
15. Low & reverse brake
16. Low one-way clutch
17. Parking pawl
The driving force from the input shaft (1) is transmitted
to the rear sun gear (5) and reverse & high clutch drum.
As in the case of the 1st gear and 2nd gear, the low
clutch (14) is engaged and the movement of the rear
internal gear (7) is restricted. Since the high clutch (11)
is engaged, the driving force from the input shaft (1) is
directly transmitted to the rear internal gear (7). As a
result, the speed of the rear sun gear (5) and the rear
internal gear (7) becomes the same as that of the input
shaft (1), so that the rear pinion gear rotates (6) not independently but together with the rear sun gear (5)
and rear internal gear (7). When decelerating, the
engine brake is applied.

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ISUZU KB P190 2007

7A3-2 ON-VEHICLE SERVICE (JR405E)
DESCRIPTION
Before performing on-vehicle service on the automatic
transmission, check that the engine idling speed and
general engine condition are normal.
For shift interlock function, if the ignition key is out of
“LOCK” position, the shift lever select button can not be
pushed. (shift lever can not be operated.)

RTW 77ASH000901

AUTOMATIC TRANSMISSION FLUID (ATF)
Inspect
Remove the transmission dipstick to check the condition
of the ATF.
Check the color and smell of the ATF.
If the ATF is abnormal color or smells burnt, replace it
and investigate the cause of trouble.
Coloor of ATF Condition Clear red Normality
Blackish discoloration Defects of power train
parts (clutches)
W hite turbidity Include water
Discoloration of red brown Deterioration of ATF

ATF LEVEL
Inspect
Hot Level
1. W arm up the engine and the transmission by driving
the vehicle on the road so that the temperature
reaches around 80 °C (176 °F).
Do not turn the engine off.
2. Park the vehicle on a level surface.
3. Apply the parking brake firmly.
4. Let the engine run at idle.
Move the select lever slowly through all the gea
r
positions.
Stop in each gear position just long enough for the transmission to engage.
5. Return the select lever to either “P” or “N”.
6. Remove the ATF level dipstick.
7. W ipe the dipstick clean with a paper towel.
8. Reinsert the dipstick and wait several seconds.
9. Remove the dipstick.
The ATF level should be inside the “H” range on the dipstick.
242R300001
If the ATF level is below the “H” range, ATF must be added.

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ISUZU KB P190 2007

ON-VEHICLE SERVICE (JR405E) 7A3-3
Cold Level
The vehicle must not have been driven so that the
temperature reaches around 20 °C (68 °F) before the
cold level check is made.
1. Park the vehicle on a level surface.
2. Apply the parking brake firmly.
3. Start the engine and allow it to warm up.
The engine coolant temperature gauge needle should be midway between the “C” mark and “H”
mark.
4. Let the engine run at idle.
Move the select lever slowly through all the gea
r
ranges.
Stop in each range just long enough for the transmission to engage.
5. Return the select lever either “P” or “N”.
6. Remove the ATF level dipstick.
7. W ipe the dipstick clean with a paper towel.
8. Reinsert the dipstick and wait several seconds.

9. Remove the dipstick.
The ATF level should be inside the “C” range on the dipstick.
If the ATF level is below the “C” range, ATF must be added.
242R300002


ATF CHANGE
1. Park the vehicle on level ground and block the rear
wheels.
2. Start the engine and allow it to idle until the ATF reaches a temperature of 40-50 °C (104-122 °F).
3. Stop the engine.
4. Raise the front to the vehicle and support with suitable safety stands.
5. Remove the drain plug from the oil pan and drain the ATF (approximately 6 liters).





6. Remove the oil pan.
7. Inspect the oil pan (details written below).
8. Install the oil pan.
Note:
Use a new gasket. Clean the oil pan and magnet.
Oil pan bolt torque : 8 N ⋅m (0.8 kgf ⋅m/69 lb ⋅in)
9. Replace the gasket and install the drain plug.
Drain plug torque : 35 N ⋅m (3.6 kgf ⋅m/26 lb ⋅ft)
Note:
Do not reuse the old washer (gasket).
Clean the drain plug (especially the threaded section).
10.Remove the safety stands and wheel blocks.
11.Pour about 5 liters of new ATF.
12. Start the engine. W ith your foot on the brake, move the shift lever through each gear range, and shift to
“P” range.
13.Check the ATF level. Add more ATF carefully as necessary using the dipstick. Refer to “ATF LEVEL”
preciously in this section.
Note:
Keep the engine idle (do not stop it) during the ATF level
adjustment.


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ISUZU KB P190 2007