2004 ISUZU TF SERIES clutch

7A2-10 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Control and Functions
Shift Control
The transmission gear is shifted according to the shift
pattern selected by the driver. In shifting gears, the
gear ratio is controlled by the ON/ OFF signal using the
shift solenoid S1 and the shift solenoid S2.
Band Apply Control
The band apply is controlled when in the 3 –2 downshift
(engine overrun prevention) and the garage shift (shock
control).
The band apply solenoid is controlled by the signal from
the Pulse Width Modulation (PWM) to regulate the flow
of the oil.
Torque Converter Clutch Control
The clutch ON/OFF is controlled by moving the
converter clutch valve through shifting Torque
Converter Clutch (TCC) solenoid using the ON/OFF
signal.
Line Pressure Control
The throttle signal allows the current signal to be sent
to the force motor. After receiving the current signal,
the force motor activates the pressure regulator valve
to regulate the line pressure.
On –Board Diagnostic System
Several malfunction displays can be stored in the
Transmission Control Module (TCM) memory, and read
out of it afterward.
The serial data lines, which are required for the testing
of the final assembly and the coupling to othe
r
electronic modules, can be regulated by this function.
Fail –Safe Mechanism
If there is a problem in the transmission system, the
TCM will go into a “backup" mode.
The vehicle can still be driven, but the driver must use
the select lever to shift gears.
Torque Management Control
The transmission control side sends the absolute spark
advance signal to the engine control side while the
transmission is being shifted. This controls the engine
spark timing in compliance with the vehicle running
condition to reduce the shocks caused by the change o
f
speed.
ATF Warning Control
The oil temperature sensor detects the ATF oil
temperature to control the oil temperature warning,
TCC, and the 3rd start mode.
Reverse Lock Out Control
With the selector lever in reverse position, the TCM will
not close the PWM solenoid until the vehicle is below
15 km/h (9.3 mph), thus preventing reverse
engagement above this speed.

Downhill Control
This mode is automatically activated from NORMAL
mode only when downhill conditions are recognized.
The shift pattern is identical to NORMAL mode except
3-4 and 4-3 shift lines at low throttle modified to get
engine braking on a larger speed range.
Uphill Control
When uphill condition are recognized the 2-3 and 3-4
shift and TCC apply are down only when the engine
torque is sufficient in order to avoid shift hunting.
Gear Shift Control 3rd start


SELECT LEVER RANGE SHIFT PATTERN
D(Drive) 1


2TCC

3TCC

4TCC
3(Third) 1

2TCC

3TCC
2(Second) 1

2(
3)
L(First) 1(
2)
TCC: Torque Converter Clutch
(Notice1): “( )" means over-revving prevention control.
Mode Type


Mode Type Select lever position
Normal drive mode
(NOR) Entire range (excluding “R")
Power drive mode
(PWR) Entire range (excluding “R")

Mode Selection



SWITCH(SW) LAMP
Mode Type PWR/N
OR.S 3RD
START SW POWER
DRIVE LAMP 3RD
START LAMP
Normal
drive mode
(NOR) OFF OFF OFF OFF
Power
drive mod
(PWR) ON OFF ON OFF
3rd Start
mode OFF ON OFF ON
However, the 3rd start switch prevails over the
PWR/NOR switch.
The mode become normal drive mode when the 3rd
start switch is operated from ON to OFF.

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-11

Comparison of mode
1. The normal drive mode is set at the normal shift
points.
2. The shift points of the power drive mode are shifted
to the higher speed side, compared to the normal
drive mode.
3. The 3rd start mode is a special mode used
exclusively for starting in third gear.
3rd start Mode
1. The 3rd start switch will operate when switched on
after all of the following conditions are present:
a. The gear select position is “D" range only.
b. Vehicle speed is 11 km/h (7 mph) or less.
c. Transmission oil temperature is 120

C (248

F)
or less.
d. Accelerator opening is at 8% or less.
2. Cancel Release
1. Cancellation by driver
a. Turning off the 3rd start mode switch
b. Shifting select position to “3", “2", or “L" (3rd
start mode is not canceled by selecting “N",
“ R", or “P")
c. Ignition key is turned off.
2. Automatic cancellation
a. When vehicle runs at 34 km/h (21mph) o
r
more for 1 second or more
b. When transmission oil temperature reaches 120

C (284

F) or above
NOTE: The mode returns to normal drive mode o
r
power drive mode after the 3rd start mode is canceled.
Backup Mode
If a major system failure occurs which could affect
safety or damage the transmission under normal
vehicle operation, the diagnostic system detects the
fault and overrides the Transmission Control Module
(TCM).
The “CHECK TRANS" light flashes to alert the driver,
and the transmission must be manually shifted as
follows:


Select lever position Gear Ratio Selected
D 4 (Fourth)
Manual 3 4 (Fourth)
Manual 2 3 (Third)
Manual L 3 (Third)
R Reverse
Shifts are firmer to prevent clutch slip and consequent
wear. The fault should be corrected as soon as
possible.

7A2-12 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Functions of Input / Output Components
Component Function
Transfer low signal Detects the transfer High/Low position.
OD Cancel signal Detects whether the cruise control unit is judged OD cancel mode.
Output revolution sensor
(Transmission) Detects the vehicle speed.
Input revolution sensor
(Transmission) Detects the input revolution (OD direct clutch drum revolution).
Engine revolution sensor Detects the engine revolution with CAN.
Throttle position signal Detects the throttle opening rate with CAN.
Neutral start switch Detects the select lever position.
Pattern select switch Detects whether the driver has selected "NORMAL" or "POWER" mode.
Brake lamp switch Detects whether the driver has pressed the brake pedal or not.
Oil temperature sensor Detects the oil temperature.




I
n
p
u t
Diagnostic start switch Starts self-diagnosis and displays a code for faulty part if any.
I
n
p
u t
/
O
u t
p
u t Data link connector When connected with Tech2 or tester, can communicate the data for function
check, etc.
Shift solenoid S1, S2 Selects shift point and gear position suited to the vehicle running condition on the
basis of TCM output.
Lock-up control solenoid SL Control the lock-up clutch suited to the vehicle running condition on the basis of TCM output.
Pressure control solenoid
STH Adjusts throttle pressure by energizing current of linear pressure control solenoid
to prevent the shift shock and to obtain shift smoothly.
"CHECK TRANS" lamp When trouble has occurred to throttle position sensor, vehicle speed sensor, or
solenoid, "CHECK TRANS" lamp is blinked to warn the driver. If also displays the
trouble code.
A/T OIL TEMP warning
lamp Lights when ATF oil temperature rises. (Turned on at greater than 146


C
(295

F). Turned off at less than 132

C (270

F).
POWER lamp Lights when POWER MODE detected.



O
u
t
p
u
t
3rd Start lamp Lights when 3rd Start MODE detected.
C
o
m
p
u t
e r Transmission Control
Module (TCM) Based on the signal from each switch and sensors, judges necessary shift point
and lock-up operation, and send signal to each solenoid.

7A2-32 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Clear DTC
NOTE: If you clear the DTC (Diagnostic Trouble
Codes) you will not be able to read any codes recorded
during the last occurrence.
NOTE: To use the DTC again to identify a problem,
you will need to reproduce the fault or the problem.
This may require a new test drive or just turning the
ignition on (this depends on the nature of the fault).
1. IF you have a Tech 2:
1. Connect the Tech 2 if it is still not connected go
through Tech 2 OBD CONNECTION.
2. Push “F1: Clear DTC Information" in the
Application Menu and answer “Yes" to the
question “Do you want to clear DTC's?"
a. When a malfunction still exists and the Tech 2 displays “AW30-40 CODES NOT
CLEARED". This means that the problem is
still there or that the recovery was not done.
Please go to DTC CHECK.
b. When a malfunction has been repaired and the recovery is done the Tech 2 displays
“ AW30-40LE CODES CLEARED".
2. When you have no Tech 2, the storaged trouble
codes can be cleared by shorting the terminals
No.11 and No.4 or 5 (ground) of data link connecto
r
with a lead wire for 1  6 seconds.
DTC Check
1. Diagnostic Trouble Codes (DTC) have been
identified by Tech 2.
2. You have written the list of the DTCs. The order o
f
the malfunctions has no meanings for this TCM.
Usually only one or two malfunctions should be set
for a given problem.
3. Check directly the DTCs you identified. The DTCs
are sorted by number. Refer to Diagnostic Trouble
Code (DTC) Identification in this section.
TCM Precaution
The TCM can be damaged by:
1. The electrostatic discharge
2. The short circuit of some terminals to voltage or to
ground.
Electrostatic Discharge Damage Description: 1. Electronic components used to control systems are often designed to carry very low voltage, and
are very susceptible to damage caused by
electrostatic discharge. It is possible for less than
100 volts of static electricity to cause damage to
some electronic components. By comparison, it
takes as much as 4,000 volts for a person to even
feel the zap of a static discharge.
2. There are several ways for a person to become
statically charged. The most common methods o
f
charging are by friction and induction. An example
of charging by friction is a person sliding across a
car seat, in which a charge of as much as 25,000
volts can build up. Charging by induction occurs
when a person with well insulated shoes stands
near a highly charged object and momentarily
touches ground. Charges for the same polarity are
drained off, leaving the person highly charged with
the opposite polarity. Static charges of either type
can cause damage, therefore, it is important to
use care when handling and testing electronic
components.
NOTE: To prevent possible electrostatic discharge
damage:
1. Do not touch the TCM connector pins or soldered
components on the TCM circuit board.
2. Be sure to follow the guidelines listed below i
f
servicing any of these electronic components:
3. Do not open the replacement part package until it is time to install the part.
4. Avoid touching electrical terminals of the part.
5. Before removing the part from its package, ground
the package to a known good ground on the
vehicle.
6.
Always touch a known good ground before handling
the part. This step should be repeated before
installing the part if the part has been handled
while sliding across the seat, while sitting down
from a standing position or while walking some
distance.
Information On TCM
1. The Transmission Control Module (TCM) is located
in the place of a clutch pedal and is the control
center of the electronic transmission control
system.
2. The TCM must be maintained at a temperature below 85

C (185

F) at all times. This is most
essential if the vehicle is put through a paint baking
process. The TCM will become inoperative if its
temperature exceeds 85

C (185

F). Therefore, it is
recommended that the TCM be removed or that
temporary insulation be placed around the TCM
during the time the vehicle is in a paint oven o
r
other high temperature process.
3. The TCM is designed to process the various inputs and then respond by sending the appropriate
electrical signals to control transmission upshift,
downshift, shift feel and torque converter clutch
engagement.
4. The TCM constantly interprets information from the
various sensors, and controls the systems that
affect transmission and vehicle performance. By
analyzing operational problems, the TCM is able to

7A2-34 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

TCM Diagnostic Trouble Codes
The following table lists the diagnostic trouble codes supported by this vehicle application. If any DTCs not listed here
are displayed by a scan tool, the scan tool data may by faulty; notify the scan tool manufacture of any DTCs
displayed that are not included in the following table.
DTC
NUMBER FLASH
CODE DTC NAME
“CHECK
TRANS"
P0560 25 System Voltage Error —
P0602 63 Transmission Control Module (TCM) Programming Error —
P0705 17 Transmission Range Sensor Circuit Malfunction ON
P0712 15 Transmission Oil Temperature Sensor Circuit Low Input ON
P0713 16 Transmission Oil Temperature Sensor Circuit Hight Input ON
P0717 14 Input Speed Sensor Signal Error ON
P0722 11 Output Speed Sensor Signal Error ON
P0743 33 Torque Converter Clutch Electrical ON
P0748 35 Pressure Control Solenoid Electrical ON
P0753 31 Shift Solenoid S1 Electrical ON
P0758 32 Shift Solenoid S2 Electrical ON
P1767 67 ECM CAN (Control Area Network) Invalid ON
P1790 61 Transmission Control Module ROM Checksum Error ON
P1791 62 Transmission Control Module RAM Error ON
U2104 65 CAN (Control Area Network) BUSS OFF ON

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-49

DTC P0717 (FLASHING CODE 14) Input Speed Sensor Signal Error

MAW060MF001501

Circuit Description
Input revolution information is provided to TCM by the
input revolution sensor. This sensor is located in the
transmission case.
The input revolution sensor is an electromagnetic pulse
pickup type that generates a speed signal according to
the revolution of the transmission OD direct clutch
drum. As a result, the sensor sends a sine wave signal
(AC) to the TCM, which converts this sine wave signal
(pulse voltage) to a RPM signal.
Condition for setting the DTC
The TCM detects following conditions at 1000
times continuously.

When the TCM detects following conditions at the
same time.
 When output speed is over 775 rpm (16 mph) at
gear position is 1st or 2nd or 3rd.

Input speed signal is no pulse while output speed
signal are 12 pulses.

OR

When the TCM output 2nd gear.
 The TCM detects no pulse of input speed senso
r
circuit signal after 3.5 sec.
(detection time: 0.03 sec at vehicle speed is 36 mph)
Action Taken When The DTC Sets

No engine torque control.
 No line pressure control.

No lock-up control.

No slope control.

Check Trans ON.
 DTC stored.

No detect DTC P0722.
Conditions For Clearing The DTC

The DTC can be cleared from the TCM history by
using a scan tool.

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