Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 658

7A1–132 AUTOMATIC TRANSMISSION (4L30-E)

WITHOUT DTC SET

1.

If you have already checked the Diagnostic
Trouble Code (DTC) and the scan tool TECH2
does not provide any DTC, and you have
reproduced the problem and no DTC was
stored:
This means that you have to check the problem
by comparing the way it should work to the
way it works now that the problem exits.

2.

To find the problem, perform the following
tests:

•

Transmission Operating Mode Test

AUTOMATIC TRANSMISSION (4L30-E) 7A1–133

TRANSMISSION OPERATING MODE TEST

Circuit Description:

The Transmission Control Module (TCM) can
controls 4L30-E operation in two modes: Power
mode, and Normal mode. The driver determines
the transmission operating mode through the
Power/Normal mode switch.
The Power mode provides better part-throttle ac-
celeration by providing earlier part-throttle upshifts.

METER 

BLK

FUSE BOX

CB-5
15A

B-24

2

H-26

8

POWER
MODE
INDICATOR

B8(20)

POWER MODE
INDICATOR
CONTROL

POWER MODE
ENABLE INPUT

B9(21)

C-96

C-96

2

C-98

1

C-98

TRANSMISSION
CONTROL
MODULE (TCM)

POWER
SWITCH

HOT IN ON OR START

RED/WHT

GRN/YEL

B-23

RED/WHT

6

D07LW023

7A1–134 AUTOMATIC TRANSMISSION (4L30-E)

TRANSMISSION OPERATING MODE TEST

IF: When you operated the Power Switch the indicator
turned ON:

YES

NO

No Problem. 

•

Install scan tool GOTHROUGH TECH2 CONNECTION.

•

Ignition switch ON.

•

Select F0: DATA LIST: POWER SWITCH.

Does TECH2 display “INACTIVE”?

YES

NO

•

Check wire for short to ground between
Transmission Control Module (TCM) connector C-96
terminal B8 and the Power Switch.

IF OK, replace the Power Switch. 

•

Press and hold down the Power Switch.

Does TECH2 display “ACTIVE”?

YES

•

Check wire for open between TCM connector C-96
terminal B8 and the Power Switch.

IF OK, replace the Powe Switch.

NO

The Power Switch is
working normally.

•

Selector lever in Park.

Does Power mode indicator stay
on all the time?

YES

NO

•

Check wire for short to ground
between TCM connector and
indicator (SEE SCHEMATIC).

IF OK, GOTO TCM MEM-CAL
REPLACEMENT.

•

Select F5: ACTUATOR TEST:
CHECK POWER LAMP?”

•

Press YES.

Does Power Mode Indicator light?

YES

NO

The system is
functioning correctly.

•

Check fuse, bulb, and wire for open between
connector C-96 terminal B9 and indicator and
between indicator and fuse.

•

Check wire for short to B+ between connector C-96
terminal B9 and indicator.

IF OK, GOTO TCM MEM-CAL REPLACEMENT.

TCM: Transmission Control Module

AUTOMATIC TRANSMISSION (4L30-E) 7A1–135

TCM PRECAUTONS

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 4000 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
of 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.

NOTICE: To prevent possible Electrostatic
Discharge damage:
(1)

Do not touch the TCM connector pins or
soldered components on the TCM circuit
board.

(2)

When handling a Mem-Cal (PROM), do not
touch the component leads, and do not
remove integrated circuit from carrier.

(3)

Be sure to follow the guidelines listed below if
servicing any of these electronic components:

(4)

Do not open the replacement part package
until it is time to install the part.

(5)

Avoid touching electrical terminals of the part.

(6)

Before removing the part from its package,
ground the package to a known good ground
on the vehicle.

(7)

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 passenger compartment and is
the control center of the electronic trans-
mission control system.

(2)

The TCM must be maintained at a temperature
below 185°F (85°C) at all times. This is most
essential if the vehicle is put through a paint
baking process. The TCM will become in-
operative 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 or 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 trans-
mission 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 prob-
lems, the TCM is able to perform a diagnostic
function by displaying DTC(s) and aid the
technician in making repairs.

PROM/MEM-CAL:
(1)

Information for a specific engine and vehicle is
programmed using an integrated circuit called
a Programmable Read-Only Memory (PROM).
It is also called a MEM-CAL (Memory Cali-
brator). This allows one model of controller to
be used for many different vehicles. The PROM
is located inside the TCM and has information
on the engine, transmission, calibration., etc.
While one TCM part number can be used by
many vehicle lines, a PROM is more specific
and must be used only with the right vehicles.
For this reason, it is very important to check
the latest parts book and Service Bulletin
information for the correct part number when
replacing a PROM.