Transmission ISUZU TF SERIES 2004 Workshop Manual

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

TCM Voltage & Resistance Check Sheet
CHECK ITEM PIN No. VALUE NOTE
VIGN A6 –A1 VIGN
Key “ON ”

A6 –A23 VIGN
Key “ON ”
Backup Power Supply A24 –A1 +B (Always)
Key “ON ”
Inhibitor (Select) SW P B20 –A1 “P ” Range VIGN Key “ON ”

Except “P ” 0V
Inhibitor (Select) SW R B1
–A1 “R ” Range VIGN Key “ON ”

Except “R ” 0V
Inhibitor (Select) SW N B8
–A1 “N ” Range VIGN Key “ON ”

Except “N ” 0V
Inhibitor (Select) SW D B7
–A1 “D ” Range VIGN Key “ON ”

Except “D ” 0V
Inhibitor (Select) SW 2 B19
–A1 “2 ” Range VIGN Key “ON ”

Except “2 ” 0V
Inhibitor (Select)SW 1 B18
–A1 “1 ” Range VIGN Key “ON ”

Except “1 ” 0V
Inhibitor (Select) SW 3 B9
–A1 “3 ” Range VIGN Key “ON ”

Except “3 ” 0V
Power SW B13
–A1 ON 0V Key “ON ”

OFF VIGN
3rd Start SW B4
–A1 ON 0V Key “ON ”

OFF VIGN
Brake SW B22
–A1 ON VIGN Key “ON ”

OFF 0V
AT Oil Temperature
Sensor A11
–A12 20
C 4.6V Engine run.

155

C 1.1V
4L Signal B21
–A1 4L 0V Key “ON ”

2H/4H VIGN
Diag SW B12
–A1 ON VIGN Key “ON ”

OFF 0V
Shift Solenoid A (S1) A16
–A1 P VIGN Engine run.

R VIGN

N VIGN

D –1 VIGN

D –2 VIGN

D –3 0V

D –4 0V

7A2-8 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

CHECK ITEM PIN No. VALUE NOTE
Shift Solenoid B (S2) A15 –A1 P 0V Engine run.

R 0V Engine run. (Without the
Reverse range lock out)
N 0V Engine run.
D –1 0V

D –2 VIGN

D –3 VIGN

D –4 0V
Lock-up Solenoid A5
–A1 ON VIGN (ex.) It is “ON ” when the
vehicle speed is more than
65km/h.
OFF 0V
Check Trans Lamp B3
–A1 ON 0V Key “ON ”
(The lamp is “ON ” for 3
second after key “ON ”)

OFF VIGN
AT Oil Temperature Lamp B11
–A1 ON 0V Key “ON ”
(The lamp is “ON ” for 3
second after key “ON ”)

OFF VIGN
Power Lamp B2
–A1 ON 0V Key “ON ”
(The lamp is “ON ” when the
Power switch is “ON ”)

OFF VIGN
3 rd Start Lamp B10
–A1 ON 0V Key “ON ”
(The lamp is “ON ” when the
3rd Start switch is “ON ”)

OFF VIGN
AT Oil Temp Sensor
Resistance A11
–A12 20

C
12k
Key “OFF ”

50

C 1.5k

155

C 293

Pressure Control Solenoid
Resistance A4
–A2 About
4 –7

(20

C)
Key “OFF ”
Speed Sensor Resistance B5 –B14 About
560

– 120
(20

C)
Key “OFF ”
Input Revolution Sensor
Resistance B6
–B16 About
560

– 120
(20

C)
Key “OFF ”
Lock-up Solenoid
Resistance A5
–A1 About
10

– 15
(20

C)
Key “OFF ”
Shift Solenoid A (S1)
Resistance A16
–A1 About
10

– 15
(20
C)
Key “OFF ”
Shift Solenoid B (S2)
Resistance A15
–A1 About
10

– 15
(20

C)
Key “OFF ”

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-9

Control System Diagram



RTW37AXF000201

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.

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-13

CAN bus systems in automatic
transmission control (AW30-40LE)
The automatic transmission control system in AW30-
40LE uses high speed CAN bus system .The individual
CAN bus systems are connected via two interfaces and
can exchange information and data. This allows control
modules that are connected to different CAN bus
systems to communicate.
High speed CAN bus
Transmission control modules in the vehicle that require
continuous, rapid communication are connected to the
high speed CAN bus. For example, the automatic
transmission is continuously notified of the current
engine load status. Since the automatic transmission
control module has to react immediately to load status
changes, rapid communication is required between the
engine control module and the automatic transmission
control module. The high speed CAN bus in the AW30-
40LE is designed as a two-wire CAN bus (twisted pair).
The wires are shielded and twisted. The transfer rate is
500 K baud.




RUW37ASF000401
Diagnosis
Electronic Diagnosis
How To Diagnose The Problem
1. To avoid incorrect diagnostics, this book needs to
be followed accurately. Unless stated, do not jump
directly to a section that could contain the
solution. Some important information may be
missed.
2. The sections in CAPITALS and bold are the main
sections that can be found in the contents.
3. The go to “
SECTION"
means to continue to check
going to the “section".
4. The go through “
SECTION"
means to go through
the “section" and then to go back to the place the
go through was written.
5. BASIC ELECTRIC CIRCUITS:
You should understand the basic theory o
f
electricity. This includes the meaning of voltage,
amps, ohms, and what happens in a circuit with an
open or shorted wire. You should also be able to
read and understand wiring diagrams.
Check Trans Indicator
Find CHECK TRANS indicator and verify if it is
A. Flashing: Go to DIAGNOSTIC CHECK.
B. Staying on: Go through CHECK TRANS CHECK
.
C. Is never ON when the ignition key is turned on: Go through CHECK TRANS CHECK
D. Is ON during 3 seconds at ignition but OFF after: Normal operation. No DTC or malfunction.



RTW37ASH000401
On Board Diagnostic Check
This test determines if the transmission or its input or
output connections or sensors are failing.
1. Connect the Tech 2: Go through Tech 2 OBD
CONNECTION .
2. Turn on the ignition but not the engine.
3. Push “F0" on Tech 2 to see the Diagnostic Trouble
Code (DTC):

7A2-14 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

4. Do you have a DTC?
YES: write down all code numbers and do the DTC
CHECK
NO: the DTC can not help you find the problem.
1. Go through “
CHECK TRANS" CHECK
2. If it is flashing and the flash is 0.4 seconds ON
and 0.4 seconds OFF, this means that you
should have a DTC stored. Please recheck go
to DIAGNOSTIC CHECK
and if you find the
same problem, replace the Powertrain Control
Module (TCM).
Normal




C07RY005-1
Abnormal





C07RY00042-1

“Check Trans" Check

1. Indicator is ON during 3 seconds at ignition but it is
OFF after the engine starts. The indicator is
working normally go to DIAGNOSTIC CHECK
.



RTW37ASH000401
Normal





C07RY005-1

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-15

2. Indicator is flashing and the flash is 0.4 seconds
ON and 0.4 seconds OFF always when ignition is
on (engine cranked or not). This means that there is
a malfunction. Go to DIAGNOSTIC CHECK
.
Abnormal





C07RY00042-1
3. Indicator is staying ON always when Ignition is ON.
1. This means that connection between the lamp
and the indicator control unit is shorted to
ground.
2. Verify if instrument panel terminal 2 o
f
connector B –23 is shorted to ground.
3. Verify if the indicator control unit connector C –
95 terminal 3 is shorted to ground.
4.
Verify that the instrument panel terminal 30 of
connector B –24 is connected to battery.
5. If problem solved: Go to CHECK TRANS
INDICATOR .
NO: Replace Transmission Control Module
(TCM).
4. Indicator is staying OFF with the ignition ON
(engine OFF).
1. This means that connection between the lamp
and the indicator control unit is shorted to
battery or opened.
2.
Verify if instrument panel terminal 2 of
connector B –23 is shorted to battery or open.
3. Verify if the indicator control unit connector C –
95 terminal 3 is shorted to battery or open.
4.
Verify that the instrument panel terminal 2of
connector B –23 is connected to battery. If not,
check the fuses and the connections (terminal
11 of connector H –6) voltage.

7A2-16 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

5. If problem solved: Go to CHECK TRANS
INDICATOR .
NO: Replace Transmission Control Module
(TCM).



RTW37LF000701