clutch ISUZU TF SERIES 2004 Workshop Manual

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-55

DTC P0743 (FLASHING CODE 33) Torque Converter Clutch Electrical


RUW37ALF000601
Circuit Description
The lock-up solenoid SL of the torque converter clutch
(TCC) controls the lock-up clutch by a signal according
to the lock-up range judgment of the TCM when the
vehicle runs.
This function can improve the fuel consumption to
almost the same extent as the manual transmission.
The lock-up solenoid SL is put into B+ by the TCM, so
that the solenoid is actuated with the result of lock-up.
Condition for setting the DTC
The TCM detects following conditions both "Condition
1" and "Condition 2" occur 2 times or more than it.
Condition 1 ("GND short"):

Voltage at connector pin is 0V for 0.3 sec
continuously when solenoid is “ON".
Condition 2 ("Open or IG short"):

Voltage at connector pin is ignition voltage for 0.5
sec continuously when solenoid is “OFF".
Action Taken When The DTC Sets

No lock-up control.
 The TCM fixes to 1st gear when the vehicle speed is
less than 6 mph.

Check Trans ON.

DTC stored.

7A2-56 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

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.5 (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
oropen condition, move the wiring harness while
observing test equipment for a change.


DTC P0743 (FLASHING CODE 33) Torque Converter Clutch Electrical


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 P0743? — Go to Step 3 Refer to
Diagnostic Aids
3

1. Key “ON", engine run.

2. Place the selector lever in the "P" range.
3. Measure the voltage between terminal C94-5 and
terminal C94-1 on the TCM pigtail connector by
J39200 DMM.
Is the voltage specified value? 816V Go to Step 4 Go to Step 10

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

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-3

Location of Clutch, Brake, One-Way Clutch and Solenoid

RUW37ALF000201

Legend
(8) One-way clutch (No.2) (F–2)
(1) Overdrive direct clutch (C–0) (9) Shift solenoid (S–1)
(2) Overdrive brake (B–0) (10) Shift solenoid (S–2)
(3) Direct clutch (C–2) (11) One-way clutch (No.1) (F–1)
(4) Second coast brake (B–1) (12) Pressure control solenoid (STH)
(5) Forward clutch (C–1) (13) Lock-up solenoid (SL)
(6) Second brake (B–2) (14) Overdrive one-way clutch (F–0)

7A3-4 ON-VEHICLE SERVICE (AW30 –40LE)

Operation of Clutch, Brake and One-Way Clutch




Transmission Identification


RUW37ASH004301
Legend
(1)
Transmission Model Number
(2)
Production Serial Number


The identification plate is located on the right rear side
of the transmission.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-5

Speed Change and Lock-Up Pattern
If you select a speed as shown below by specifying
respective positions of transmission shift lever, transfe
r
switch and pattern select switch, the transmission
control computer controls speed change and lock-up
operations based on the specified pattern in accordance
with the degree of throttle opening and vehicle speed.
Pattern select sw. position Transmission shift position


D 3 2 L
NORMAL, POWER 1st 
[2nd] 
[3rd] 
[O/D] 1st 
[2nd] 
[3rd] 1st 
2nd
(3rd) 1st
(2nd)
3rd START 3rd fixing — —

[ ]: The lock-up operation is available.
( ): Transmission is shifted at high speed to prevent overrun.


Overdrive and Lock-Up Operating Conditions
The overdrive and lock-up clutch operate if the following
conditions are satisfied.
Overdrive Lock-up clutch
Shift pattern position
NORMAL NORMAL
Transmission shift position
D range 
Brake lamp switch
— OFF
Throttle opening
Fully closed Except fully closed
Accelerator About 52 km/h (32 mph) or more 2nd: About 76 km/h (47 mph) or
more
Vehicle speed Deceleration About 42 km/h (26 mph) or more 3rd: About 56 km/h (35 mph) or more
O/D: About 67 km/h (42 mph) or
more

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) 7A3-35

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

7A3-50 ON-VEHICLE SERVICE (AW30 –40LE)

Major Components
Disassembly, inspection and reassembly of each
component group is indicated in the following chapter.
Before reassembly, make sure, again, that all
component groups are assembled correctly.
If something wrong is found in a certain component
group during assembly, inspect and repair this group
immediately.
General Assembly Notes:
1. The automatic transmission is composed of highly
precision-finished parts, necessitating careful
inspection before assembly because even a small
nick could cause fluid leakage or affect
performance.


2. Before assembling new clutch discs and brake
bands, soak them in automatic transmission fluid fo
r
at least thirty minutes.
3.
Apply automatic transmission fluid on the sliding or
rotating surfaces of parts before assembly.
4. Use petroleum jelly to keep small parts in thei
r
palces.
5. Do not use adhesive cements on gaskets and similar parts.
6. When assembling the transmission, be sure to use new gaskets and O-rings.
7. Dry all parts with compressed air - never use shop rags.
8. Be sure to install the thrust bearings and races in the correct direction and position.



Bearing and Race

RUW36AM F000201