ISUZU KB P190 2007 Workshop Repair Manual

7A3-6 ON-VEHICLE SERVICE (AW30–40LE)




A/T : Automatic Transmission



BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ON-VEHICLE SERVICE (AW30–40LE) 7A3-7








BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

7A3-8 ON-VEHICLE SERVICE (AW30–40LE)









BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ON-VEHICLE SERVICE (AW30–40LE) 7A3-9
Manual Shifting Test
NOTE: W ith this test, it can be determined whether the
trouble lies within the electrical circuit or is a mechanical
problem in the transmission.
1. Disconnect TCM connector
2. Inspect manual driving operation
Check that the relation of the position between
select lever and gear corresponds to the following
table.
If any abnormality is found in the above test, do
perform the stall, time lag or gear shift tests.







RTW 77ASH002901
3. Connect TCM connector
W ith the engine off, connect the TCM connector.


Stall Test





RTW 67ALH000101
The object of this test is to check the overall
performance of the transmission and engine b
y
measuring the maximum engine speeds at the “D" and
“R" positions.
NOTE:
1. Perform the test at normal operating fluid
temperature (50 – 80 °C or 122 – 176 °F).
2. Do not continuously run this test longer than 5 seconds.





BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

7A3-10 ON-VEHICLE SERVICE (AW30–40LE)
Measure Stall Speed
1. Chock the four wheels.
2. Mount an engine tachometer.
3. Fully apply the parking brake.
4. Step down strongly on the brake pedal with your left foot. (Keep the state until the test is completed)
5. Start the engine.
6. Turn off the A/C.
7. Select into the “D" position. Step all the way down on the accelerator pedal with your right foot. Quickl
y
record the highest speed as soon as the engine
speed gets stabilized.
8. Select into the “N” position and maintain the engine
idling condition more than 1 minute.
Stall speed: 2300 ±
±±
±
200 rpm *
* Ambient temperature to be between roughly 10 °C
(50 °F) and 40 °C (104 °F).
Evaluation
1. If the engine speed is the same for both positions
but lower than the specified value:
• Engine output is insufficient.
• Stator one-way clutch is not operating properly.
NOTE: If more than 600 rpm below the specified value,
the torque converter could be faulty.
2. If the stall speed in “D" position is higher than
specified:
• Line pressure too low
• Forward clutch slipping
• No.2 one-way clutch not operating properly
3. If the stall speed in “R" position is higher than
specified:
• Line pressure too low
• Direct clutch slipping
• No.3 brake slipping
4. If the stall speed in the “R" and “D" positions are
higher than specified:
• Line pressure too low
• Improper fluid level

Time Lag Test



F07RY00003
If the shift lever is shifted while the engine is idling,
there will be a certain time elapse or lag before the
shock can be felt. This is used for checking the
condition of the forward clutch, direct clutch, No.3
brake, and No.2 one-way clutch.
NOTE:
1. Perform the test at normal operating fluid
temperature (50 – 80 °C or 122 – 176 °F)
2. Be sure to allow one minute interval between tests.
3. Make three measurements and take the average value.




BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ON-VEHICLE SERVICE (AW30–40LE) 7A3-11
Measure Time Lag
1. Fully apply the parking brake.
2. Start the engine. Check idling speed (A/C OFF).
3. Operate the select lever from “N" to “D" position.
Using a stopwatch, measure the time it takes from
shifting the lever until the shock is felt.
Time lag: Less than 0.7 seconds
4. In same manner, measure the time lag for “N" →
“R".
Time lag: Less than 1.2 seconds
Evaluation
1. If “N" → “D" time lag is longer than specified:
• Line pressure too low
• Forward clutch malfunction
• No.2 one-way clutch not operating properly
2. If “N" → “R" time lag is longer than specified:
• Line pressure too low
• Direct clutch malfunction
• First and Reverse brake malfunction
3. If both time lag is longer than specified:
• Line pressure too low

Hydraulic Test






RTW 67ALH000201
Preparation
1. W arm up the transmission fluid.
2. Remove the transmission case test plug and mount the hydraulic pressure gauge.
Oil pressure gauge: 5-8840-0093-0
NOTE: Perform the test at normal operating fluid
temperature (50 – 80 °C or 122 – 176 °F).




BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

7A3-12 ON-VEHICLE SERVICE (AW30–40LE)
Measure Line Pressure
1. Fully apply the parking brake and chock the four
wheels.
2. Start the engine and check idling rpm.
3. Select into “D" position, step down strongly on the brake pedal with your left foot and while
manipulating the accelerator pedal with the right
foot, measure the line pressures at the engine
speeds specified in the table.
4. In the same manner, perform the test in “R" position.


Line pressure kPa (kg/cm
2/psi) Engine
speed “D" position “R" position
Idling 349 – 408
(3.6 – 4.2 /51 – 59) 577 – 675
(5.9 – 6.9/84 – 98)
Stall 1,206 – 1,353
(12.3–13.8/175–196) 1,646 – 1,979
(16.8–20.2/239–287)

Evaluation
1. If the measured values at all positions are higher
than specified:
• Pressure control solenoid defective
• Primary regulator valve defective
2. If the measured values at all positions are lowe
r
than specified:
• Primary regulator valve defective
• Oil pump defective
• Pressure control solenoid defective
3. If pressure is low in “D" position only:
• “D" position circuit fluid leakage
4. If pressure is low in “R" position only:
• “R" position circuit fluid leakage
Road Test
NOTE: Perform the test at normal operating fluid
temperature (50 – 80 °C or 122 – 176 °F).
“D" Position Test in “NORMAL", and
“POWER" Pattern
Select into the “D" position and hold the accelerator
pedal constant at the 50% and 100% throttle valve
opening positions.
Push in one of the pattern selector buttons and check
the following:

1. 1–2, 2–3, 3–OD and lock-up, upshifts should take
place, and shift points should conform to those
shown in the automatic shift diagram.


RTW 77ASH003001



RUA37ASH000101



BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ON-VEHICLE SERVICE (AW30–40LE) 7A3-13
Evaluation
i. If there is no 1→2 upshift:
• Solenoid S2 is stuck
• 1–2 shift valve is stuck
ii. If there is no 2 →3 upshift:
• Solenoid S1 is stuck
• 2–3 shift valve is stuck
iii. If there is no 3 →OD upshift (throttle valve opening
1/2):
• Solenoid S2 is stuck
• 3–OD shift valve is stuck
iv. If the shift point is defective: Refer to TROUBLESHOOTING CHART in this
section.
v. If the lock-up is defective: Refer to TROUBLESHOOTING CHART in this
section.
2. In the same manner, check the shock and slip at the 1→ 2, 2 →3 and 3 →OD upshifts.
NOTE: Drive the vehicle on level ground.
Evaluation
If the shock is excessive:
Refer to TROUBLESHOOTING CHART in this section. 3. Run at “D" position lock-up or OD gear and check fo
r
abnormal noise and vibration.
NOTE: The check for the cause of abnormal noise and
vibration must be made with extreme care as it could
also be due to loss of balance in the propeller shaft,
differential, the torque converter, etc. or insufficient
bending, rigidity, etc. in the power train.




RUW 37ASH000201

4. W hile running in “D" position, 2nd, 3rd gears and
OD, check to see that the possible kick-down
vehicle speed limits for 2 →1, 3 →1, 3 →2, OD →3
and OD →2 kick-downs conform to those indicated
on the automatic shift diagram.




RTW 77ASH003101
5. Check for abnormal shock and slip at kick-down.
6. W hile running in “D" position, OD gear or “lock-up", shift to “2" and “L" positions and check the engine
braking effect at each of these positions.


BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

7A3-14 ON-VEHICLE SERVICE (AW30–40LE)
Evaluation
i. If there is no engine braking effect in the “2"
position:
• Second coast (No.1) brake is defective.

ii. If there is no engine braking effect in the “L" position:
• First and reverse (No.3) brake is defective.







RUW 37ASH000301
iii. Also check to see that downshift is made from 3 to
2 or from OD to 3 and then to 2 immediately and
that 2 →1 downshift point is within the limits shown
in the diagram when tested by releasing the
accelerator pedal and operaing into “L" position
while driving in the third gear or in overdrive.




RUW 37ASH000401

“2" Position Test
Select into “2" position and, while driving with the
accelerator pedal held constantly at the specified point
(throttle valve opening 50% and 100%), push in one o
f
the pattern selectors and check on the following points.
1.
At each of the above throttle openings, check to see
that the 1 →2 upshift takes place and that the shift
points conform to those shown on the automatic
shift diagram.
NOTE: There is no OD and no lock-up in the “2"
position.




RTW 77ASH003201
2. W hile running in the “2" position and 2nd gear,
release the accelerator pedal and check the
engine's braking effect.
3. Check for 2 →1 downshift and abnormal noise at
acceleration and deceleration, and for shock at
upshift and downshift.







RUW 37ASH000501


BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ON-VEHICLE SERVICE (AW30–40LE) 7A3-15
“L" Position Test
1. W hile running above 80 km/h (50 mph) in the “D"
position, release your foot from the accelerato
r
pedal and shift into the “L" position.
Then check to see that the 2 →1 downshift occurs at
the specified point shown on the automatic shift
diagram.




RUW 37ASH000601
2. W hile running in the “L" position, check to see that
there is no upshift to 2nd gear.
3. W hile running in the “L" position, release the accelerator pedal and check the engine braking
effect.
4. Check for abnormal noise during acceleration and deceleration.








RUW 37ASH000701

“R" Position Test
Select into the “R" position and, while starting at full
throttle, check for slipping.





RUW 37ASH000801
“P" Position Test
Stop the vehicle on a grade (more than 9%) and afte
r
shifting into the “P" position, release the parking brake.
Then check to see that the parking lock pawl holds the
vehicle in place.



BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007