Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 291

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-13

CONTROL AND FUNCTIONS

Item Description

Shift and lock-up control

• In D range, speed change point and Lock-up point can be

changed by setting pattern selection switch to "POWER",
"NORMAL" or "WINTER (UBS)" mode.

• Gear shift position in the conditions made up of transmission shift

positions (D.2.L) combined with pattern selection switch
(POWER, NORMAL, and WINTER) can be controlled in
accordance with vehicle speed and the opening of throttle valve.

Overdrive cut control

• If O/D switch is set on in D range (O/D OFF lamp ON), gear shift

to O/ D is not effected.

• Overdrive is released at O/D switch on and high transmission oil

temperature (More than 130

°C).

However, to prevent engine over revolution

• 4→3 shifting at vehicle speed is less than 118 km/h (UBS) or

117 km/h (TF).

• 3→4 shifting at vehicle speed is more than 131 km/h (UBS) or

125 km/h (TF) or 120 km/h (‘01TFR for Thailand).

Lock-up cut control

• In D range, 2nd (TF), 3rd or O/D lock-up is conducted in

"POWER" or "NORMAL" mode.

• In 2, L range, lock-up is off in the whole area.
• Lock-up is released at brake on or high transmission oil

temperature
(More than 130

°C  UBS and 01’TFR for thailand)

.

(More than 140

°C  TF).

• Lock-up is prohibited while driving in coasting condition.

Driving mode select control

• The TCM selects a suitable driving mode from the nine kinds for

the variety driving condition.

i) Economy mode ii)Power mode iii)Winter mode(UBS) iv)HOT1

mode v)HOT2 mode vi)L4 mode(4

×4) vii)Slope mode(UBS)

(Up slope 1, Up slope 2 and Down slope mode)

• The priority of driving mode:
Economy < Power < Slope(UBS) < L4(4

×4) < Winter(UBS) <

HOT1 < HOT2

Squat control

• When the TCM detects D signal on, the TCM controls 1–3–1 shift

by setting a timer, in order to improve the shift feel at N

→D.

Line pressure control

• The TCM output current which corresponds to throttle oil

pressure to pressure control solenoid based on throttle opening.

Indicate oil temperature warning function

• If the transmission oil temperature sensor senses that

transmission oil temperature is greater than 146

°C, the TCM turn

on A/T OIL TEMP warning lamp. (The warning lamp is turned off,
if oil temperature is less than 126

°C.)

L4 mode control (4

×4)

• The TCM judges whether the transfer is engaged in high or low

based on the ratio rpm data from output speed sensor in the
transmission and the rpm data from speed meter sensor to select
the shift map.

Up and down hill control (UBS)

• The TCM judges up and down hill, and change shift pattern

based on throttle opening and acceleration.

7A-14 AUTOMATIC TRANSMISSION (AW30-40LE)

CONTROL AND FUNCTIONS (Cont’d)

Item Description

Correct oil temperature control

• If the temperature exceeds a predetermined value, the TCM

selects the high oil temperature shift point for downshifting, thus
preventing the oil temperature from rising. (More than 130

°C, D

range – UBS and ’01 TFR for Thailand) (More than 140

°C, D

range – ’02 TF)

Winter mode control (UBS)

• The TCM controls the vehicle start smoothly on low frictional road

like snow road by executing this control.

Activate condition:
When all following conditions are satisfied and winter mode switch
ON, winter mode is activated on “D” range. (Winter mode ON is
judged at the time of switch release after switch ON condition is 200
ms continuously or more.)
1. Excluding "2", "L" range
2. Vehicle speed is less than 11 km/h
3. Transmission oil temperature is less than 115

°C

4. Throttle opening is less than 8%
5. Excluding winter mode
Cancel condition:
When at least one among the following five conditions is satisfied,
the winter mode is canceled.
1. When winter mode switch is pushed again
2. When either "2" or "L" is detected
3. Ignition switch "OFF"
4. Vehicle speed is more than 34 km/h for 1 second or mode

continuously

5. Transmission oil temperature is more than 130

°C

Fail-safe function

• When trouble occurs to vehicle sensor and each solenoid, TCM

automatically exerts fail-safe control not to spoil driveability.

• This control is exerted when sensor or actuator is in trouble, while

TCM works normally.

Diagnosis function

• If there is an abnormality in vehicle sensors, each solenoid (S1-

S3, STH), or throttle position sensor, "CHECK TRANS" lamp is
actuated to warn the drive. But when the abnormality items have
been restored to normal, the light does not blink.

• Faulty parts are memorized in TCM. If self-diagnosis start signal

is inputted, "CHECK TRANS" lamp is blinked and results of
diagnosis are indicated. A history of faults remains recorded even
when IGN switch is off.

TECH 2

• Output of control data in the TCM
• Actuator (Solenoid) operation check
• Erasure

of

trouble

code

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-15

MAJOR INPUT/OUTPUT COMPONENTS

Component Function

Vehicle speed sensor (Speedometer)

Detects the vehicle speed (Back-up sensor of output revolution
sensor).

Output revolution sensor (Transmission)

Detects the vehicle speed

Input revolution sensor (Transmission)

Detects the input revolution (O/D direct clutch drum revolution).

Engine revolution sensor

Detects the engine revolution.

Throttle position sensor

Detects the throttle opening rate.

Neutral start switch

Detects the select lever position.

Pattern select switch

Detects whether the driver has selected "NORMAL",
"POWER", or "WINTER" (UBS) mode.

Overdrive switch

Detects whether the driver has selected O/D.

Brake lamp switch

Detects whether the driver has pressed the brake pedal or not.

Oil temperature sensor

Detects the oil temperature.

Inpu

t

Diagnostic start switch

Starts self-diagnosis and displays a code for faulty part if any.

In

pu

t/

Out

put

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. Turned off at less than 126°C.)

Power mode lamp

Informs the driver whether the vehicle is in power mode or not.

Ou

tp

ut

Winter mode lamp (UBS)

Informs the driver whether the vehicle is in winter mode or not.

Co

mp

ut

er

Transmission Control Module (TCM)

Based on the signals from each switch and sensor, judges
necessary shift point and lock-up operation, and send signal to
each solenoid.

7A-16 AUTOMATIC TRANSMISSION (AW30-40LE)

LOCATION OF CLUTCH, BRAKE, ONE-WAY CLUTCH AND SOLENOID

UBS AND TFR/S

C07R200022