fluid ISUZU TF SERIES 2004 Manual Online

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-59


DTC stored.
Conditions For Clearing The DTC

The DTC can be cleared from the TCM history by
using a scan tool.
 The DTC will be cleared from history when the
vehicle has achieved 40 warm-up cycles without a
failure reported.

After more than 1 second has elapsed after the
ignition key has been turned “ON", short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.
Diagnostic Aids

Inspect the wiring for poor electrical connection at
the TCM. Look for possible bent, backed out,
deformed or damaged terminals. Check for weak
terminal tension as well. Also check for a chafed wire
that could short to bare metal or other wiring.
Inspect for a broken wire inside the insulation.

When diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.


DTC P0748 (FLASHING CODE 35) Pressure Control Solenoid Malfunction


Step Action Value(s) YES NO
1
Was the Powertrain On-Board Diagnostic (OBD)
System Check performed? — Go to Step 2 Go to OBD
System Check
2

1. Install the scan tool.

2. Key “ON".
3. Review and record scan tool data.

4. Operate the vehicle within scan tool data.
Does the scan tool indicate DTC P0748? — Go to Step 3 Refer to
Diagnostic Aids
3 Perform the transmission fluid checking procedure.
Refer to checking Transmission Fluid level and
Condition in Automatic Transmission 7A section.
Was the fluid checking procedure performed? — Go to Step 4 Refer to
checking
Transmission
Fluid level and
Condition in
Automatic
Transmission
(AW30-40LE)
section

ON-VEHICLE SERVICE (AW30–40LE) 7A3-1
TRANSMISSION
ON-VEHICLE SERVICE (AW30–40LE)
CONTENTS

Service Precaution .................................................
7A3-2
Location of Clutch, Brake, One-Way Clutch
and Solenoid ........................................................
7A3-3
Operation of Clutch, Brake and One-Way
Clutch ....................................................................
7A3-4
Trnasmission Indentification ..............................
7A3-4
Speed Change and Lock-Up Pattern ...............
7A3-5
Overdrive and Lock-Up Operating
Conditions ............................................................
7A3-5
Diagnosis .................................................................
7A3-6
Basic Troubleshooting ........................................
7A3-6
Manual Shifting Test ...........................................
7A3-12
Stall Test ..............................................................
7A3-12
Time Lag Test .....................................................
7A3-13
Hydraulic Test ......................................................
7A3-14
Road Test .............................................................
7A3-15
Shift Pont Chart and Lock-Up Point Chart ..........
7A3-19
Shift Pont Chart ...................................................
7A3-19
Lock-Up Point Chart ...........................................
7A3-20
Transmission Fluid Level and Condition .............
7A3-21
Inspection .............................................................
7A3-21
ATF Replacement ..................................................
7A3-22
Inspection .............................................................
7A3-22
Neutral Start Switch (Mode Switch) .....................
7A3-23
Inspection .............................................................
7A3-23
Removal ...............................................................
7A3-23
Installation ............................................................
7A3-23
Brake Signal ............................................................
7A3-24
Inspection .............................................................
7A3-24
Input and Output Revolution Sensor ....................
7A3-25
Inspection .............................................................
7A3-25
Pattern Select Switch .............................................
7A3-25
Inspection .............................................................
7A3-25
Solenoid ...................................................................
7A3-26
Inspection .............................................................
7A3-26

ATF Temperature Sensor ......................................
7A3-27
Inspection .............................................................
7A3-27
Select Lever ....................................................... 7A3-28 Remove or Disconnect .......................................
7A3-28
Install or Connect .................................................
7A3-29
Shift Cable ......................................................... 7A3-31
Remove or Disconnect .......................................
7A3-31
Install or Connect .................................................
7A3-32
Torque specifications ..........................................
7A3-33
Transmission Control Module (TCM) ...................
7A3-34
Removal ................................................................
7A3-34
Installation .............................................................
7A3-34
Shift Solenoid and Lock-Up Solenoid ...................
7A3-35
Removal ................................................................
7A3-35
Installation .............................................................
7A3-36
Valve Body Assembly and Pressure Control Solenoid .................................................
7A3-37
Removal ................................................................
7A3-37
Installation .............................................................
7A3-39
Rear Oil Seal (Adapter Housing, 4

4) .................
7A3-40
Removal ................................................................
7A3-40
Installation .............................................................
7A3-40
Rear Oil Seal (Extension Housing, 4
2) ..............
7A3-41
Removal ................................................................
7A3-41
Installation .............................................................
7A3-41
Transmission Assembly .........................................
7A3-42
Transmission and Associated Parts .................
7A3-42
Removal ................................................................
7A3-43
Installation .............................................................
7A3-46
Major Components ..............................................
7A3-50

7A3-12 ON-VEHICLE SERVICE (AW30 –40LE)

Manual Shifting Test
NOTE: With 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
Inspect manual driving operation
2. Inspect manual driving operation
Check that the shift and gear positions correspond
with the table.
If the “L", “2", “3" and “D" range gear positions are
difficult to distinguish, do perform the following road
test.
While driving, shift through the “L", “2", “3" and “D"
ranges. Check that the gear change corresponds to
the gear position.
If any abnormality is found in the above test, do
perform the stall, time lag or gear change tests.



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3. Connect TCM connector
With the engine off, connect the TCM connector.


Stall Test



RUW37ALH000101
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" ranges.
NOTE:
1. Perform the test at normal operation fluid
temperature (50 – 80 
C or 122 – 176 
F).
2. Do not continuously run this test longer than 5 seconds.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-13

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.
5. Start the engine.
6. Turn off the A/C.
7. Shift into the “D" range. Step all the way down on
the accelerator pedal with your right foot. Quickl
y
read the highest engine rpm.
Stall speed: 2100






150 rpm
8. Perform the same test in the “R" range.
Evaluation

1. If the engine speed is the same for both ranges 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" range 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" range 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" ranges 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 operation 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.

7A3-14 ON-VEHICLE SERVICE (AW30 –40LE)

Measure Time Lag
1. Fully apply the parking brake.
2. Start the engine. Check idling speed (A/C OFF).
3. Shift the shift lever from “N" to “D" range. 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
 No.3 brake malfunction
3. If both time lag is longer than specified:

Line pressure too low

Hydraulic Test



RUW37ALH000201
Preparation

1. Warm up the transmission fluid.
2. Remove the transmission case test plug and mount the hydraulic pressure gauge.
Oil pressure gauge: J –29770 –A
NOTE: Perform the test at normal operation fluid
temperature (50 – 80 
C or 122 – 176 
F).

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-15

Measure Line Pressure
1. Fully apply the parking brake and chock the four
wheels.
2. Start the engine and check idling rpm.
3. Shift into “D" range, 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" range.


Line pressure kPa (kg/cm2/psi) Engine
speed “D" range “R" range
Idling 323 – 382
(3.3 – 3.9/47 – 55) 500 – 598
(5.1 – 6.1/73 – 87)
Stall 1,137 – 1,274 (11.6–13.0/165–185) 1,499 – 1,833
(15.3–18.7/218–266)
Evaluation
1. If the measured values at all ranges are higher than
specified:

Pressure control solenoid defective
 Primary regulator valve defective
2. If the measured values at all ranges are lower than
specified:

Primary regulator valve defective
 Oil pump defective
 Pressure control solenoid defective
3. If pressure is low in “D" range only:

“ D" range circuit fluid leakage
4. If pressure is low in “R" range only:

“ R" range circuit fluid leakage
Road Test
NOTE: Perform the test at normal operation fluid
temperature (50 – 80 
C or 122 – 176 
F).
“D" Range Test in “NORMAL", and
“POWER" Pattern Ranges
Shift into the “D" range 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, up-shifts should take
place, and shift points should conform to those
shown in the automatic shift diagram.


RUA370MH000101




RUA37ASH000101

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-21

Transmission Fluid Level and Condition
Inspection
Park vehicle on level ground and set parking brake.
With the engine idling, move the shift lever through all
positions from “P" to “L", then return to position “P".
Check to see if the level of fluid comes to “HOT" range
of about 80 
 

C (176 
 

F) on the dipstick gauge.
If the level of fluid is too low, replenish to bring it to
maximum level in “HOT" range.
Inspection of fluid condition. If the ATF is black o
r
smells burnt, replace it.



RUW37ASH002501

7A3-22 ON-VEHICLE SERVICE (AW30 –40LE)

ATF Replacement
Inspection
NOTE: Do not overfill.
1. Remove the drain plug from oil pan and drain the
fluid.




RUW17ASH013401
2. Reinstall the drain plug securely.
Torque: 19 N 


m (14 Ib ft)
3. With the engine OFF, add new fluid through the fille
r
tube.



Drain and refill 5.2 liter
Dry fill 8.7 liter
Fluid BESCO ATF III
4. Start the engine and shift the selector into all
position from “P" through “L", and then shift into “P".
5. With the engine idling, check the fluid level. Add fluid up to the “COLD" level on the dipstick.
6. The ATF level must be checked again for correct level with the “HOT" level.
NOTE: To prevent fluid leaks, the drain plug gasket
must be replaced each time this plug is removed.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-35

Shift Solenoid and Lock-Up Solenoid
Removal
Preparation:

Disconnect negative ( –) battery cable.
 Drain the fluid.
Refer to ATF REPLACEMENT in this section.
1. Remove oil lever gage and oil filler tube.
2. Support transfer case (4
4) or rear cover (42)
with a transmission jack.
3. Remove engine rear mounting nuts.


F07RW008
4. Remove fule pipe heat protector on tansmission
corssmenber.
5. Remove fuel pipe from the crossmenber.
6. Remove transmission crossmenber.
7. Remove the nineteen bolts.
8. Remove oil pan, using seal cutter J –37228.



RUW37ASH002901

NOTE: Do not turn over the transmission as this will
contaminate the valve body with foreign materials in the
bottom of the oil pan.
Remove oil pan by lifting the transmission case.
Oil pan seal cutter: J –37228
Examine particles in oil pan
Remove the magnet and use it to collect any steel
chips.
Look carefully at the chips and particles in the oil
pan and on the magnet to anticipate what type o
f
wear you will find in the transmission:
Steel (magnetic) ..................bearing, gear and
clutch plate wear
Brass (non-magnetic) ..........bushing wear



240RY00008
9. Remove the oil strainer assembly.



244RY00003

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-37

Valve Body Assembly and Pressure Control Solenoid





244RY00009
Removal
Preparation:


Disconnect negative ( –) battery cable.
 Drain the fluid.
Refer to ATF REPLACEMENT in this section.
1. Remove the nineteen bolts and oil pan.