Isuzu N-Series. Manual - part 936

Transmission Control System (Smoother) 7A-199

Repair Instructions

Transmission Control Module (TCM) 
Replacement

TCM Replacement Procedure Description

The following A-F steps provide an overview procedure
to replace and reprogram a TCM. Each A-F step is
explained further in this section.

A. Record the vehicle type information manually from

the old TCM. The vehicle type information can be
obtained using the Tech 2 Data Display function.

B. Replace the old TCM with the new TCM.

C. Program the latest software and calibrations into

the new TCM using the Service Programming
System (SPS).

D. Program the recorded vehicle information into the

new TCM using the Tech 2 Programming function.

E. Perform the transmission gear position learning,

half clutch learning and number of speedometer
driven gear teeth learning by initial learning
procedure.

F. Program the vehicle identification number (VIN). If

the TCM from another vehicle is installed, VIN
does not match with the vehicle. Use the SPS to
change the original VIN.

A. Recording Vehicle Information

The following vehicle type information must be
programmed into the TCM for correct vehicle
performance.

• Engine Type
• Transmission Type
• Speedometer Driven Gear Teeth
• PTO Request Engine Speed (If so equipped)

Important:
If the communications cannot be established with the
old TCM, the technician will need to follow the following
ways.

• Find out the correct engine type and transmission

type from the service ID plate.

• Physically find out the correct number of

speedometer driven gear teeth.

• Ask the customer which of the PTO request engine

speed was previously being used.

B. Removal and Installation

Removal Procedure

Important:
Take care not to give a strong impact to the TCM.

1. Turn OFF the ignition. 
2. Disconnect the negative battery cable.
3. Disconnect the TCM connectors.
4. Remove the TCM fixing nuts.

5. Remove the TCM.

Installation Procedure

Important:
Do not use a fallen TCM or the TCM that received a
strong impact.

1. Install the TCM on the TCM bracket.
2. Tighten the TCM fixing nuts.
3. Connect the TCM connectors.
4. Connect the negative battery cable. 

C. Programming Software and Calibrations

Program latest software/calibrations if released. Refer
to Service Programming System (SPS) Description and
Service Programming System (SPS) (Remote
Procedure) or Service Programming System (SPS)
(Pass-Thru Procedure) in this section.

D. Programming Vehicle Information

Use the Tech 2 to program the previously recorded
vehicle information.

Notice:
If the removed TCM from another vehicle is installed
with same specification, this programming is not
necessary.

1. Install the Tech 2.
2. Turn ON the ignition, with the engine OFF.
3. Select Diagnostics > appropriate vehicle

identification > Smoother > Programming.

4. Select Program Vehicle Type and press Change.
5. Select previously recorded correct combination of

engine type and transmission type.

Legend

1. TCM
2. TCM Cover

2

1

N7A2142E

7A-200 Transmission Control System (Smoother)

6. Select PTO Request Engine Speed and press

Change. (If PTO is not installed, skip to step 8.)

7. Select previously recorded correct PTO request

engine speed.

8. Select Program Speedometer Driven Gear and

press Change.

9. Select previously recorded correct number of

speedometer driven gear teeth.

10. Select Diagnostics > appropriate vehicle

identification > Smoother > Data Display. At this
point, all programmed data can be verified.
Compare the vehicle information programmed into
the TCM with the recorded value. If the
programmed vehicle information is incorrect, go
back to appropriate step.

E. Initial Learning

As for initial learning, transmission gear select & shift
position learning, half clutch position learning and
speedometer driven gear learning will be performed at
the same time.

1. Put the vehicle with the following conditions:

• DTC is not present
• Vehicle is stationary
• Parking brake is pulled
• Selector lever is Neutral
• Emergency switch is OFF
• Engine is warm upped
• Engine is idle speed
• Idle up control knob to the lowest position (Full

counterclockwise direction)

• A/C switch is OFF
• Use the Tech 2 and make sure clutch fluid

temperature is 40

°C (104°F) or higher

2. Use a jumper wire and the DLC terminal “11”

(diagnostic request) is pulled “Low” (grounded) by
jumped to DLC terminal “4”. This will warning lamp
blinks.

3. Depress and hold the brake pedal.

Notice:
DO NOT release the brake pedal until the transmission
gear select & shift position learning and half clutch
position learning is completed (until step 6).

4. Press Reset switch for at least 7 seconds and

release it within 17 seconds. This will enter the
learning mode, which is indicated by a buzzer
pattern that consists of a series of two short beeps.

Notice:
If the buzzer does not sound, restart the learning
procedure from step 1.

5. With the brake pedal firmly depressed, operate the

selector lever in the following sequence: N - D - N
(Neutral - Drive - Neutral)
This will change the buzzer pattern that consists of
a series of two beeps, one short beep followed by
one long beep. After the selector lever is operated,
this buzzer pattern will continue for approximately
10 seconds and shift to each gear will be
automatically performed. And then, change
automatically to single short beeps. This buzzer
pattern will continue for approximately 30 seconds
and the clutch will be automatically engaged.

Notice:
If the buzzer does not sound, operate the selector lever
again.

Notice:
If the buzzer stops on the way of this step, restart the
learning procedure from step 3.

6. Confirm that the buzzer stops. Remove the jumper

wire from the DLC.

Notice:
If the buzzer sounds after removing the jumper wire from
the DLC, restart the learning procedure from step 1.

7. Confirm that the warning lamp. The warning lamp

will blink if the number of speed meter driven gear
teeth leaning is not completed.

Notice:
If the TCM from another vehicle is installed, the warning
lamp does not blink.

8. With the parking brake applied, the engine speed

is idle, and the brake pedal is depressed, move the
selector lever to D (Drive) position. Confirm that the
gear position indicator is 2nd. If the gear position is
not 2nd, operate the selector lever “+” or “

−” to

change 2nd.

9. Run the vehicle in 2nd gear at fixed vehicle speed

of approximately 20km/h (12MPH) for 10 seconds.

10. Confirm that the warning lamp goes out.

Notice:
If the warning lamp does not go out, restart the learning
procedure from step 8.

F. Programming VIN

If the TCM from another vehicle is installed, VIN does
not match with the vehicle. Use the SPS to change the
original VIN. Refer to Service Programming System
(SPS) Description and Service Programming System
(SPS) (Remote Procedure) or Service Programming
System (SPS) (Pass-Thru Procedure) in this section.

Notice:
If an updated software/calibrations is released, DO NOT
program the VIN now. The VIN is programmed at
previously described C. Programming Software and
Calibrations SPS procedure.

Transmission Control System (Smoother) 7A-201

Service Programming System (SPS)
Description

The service programming system (SPS) allows a
technician to program a control module through the data
link connector (DLC). The information transfer circuit
that is used at the DLC is the same serial data circuit
used be the Tech 2 for retrieving diagnostic trouble
codes (DTCs), displaying data, clearing DTCs etc. This
procedure offers the ability to install software/
calibrations matched to a particular vehicle.
Most control modules have two types of memory. The
software/calibrations reside in the flash memory. The
two types of memory are listed below:

• Electrically Erasable Programmable Read Only

Memory (EEPROM).
This type of memory allows selected portions of
memory to be programmed while other portions
remain unchanged.
Certain learned values reside in the EEPROM,
such as:

– The vehicle identification number (VIN)
– The vehicle type information
– The gear position leaning and half clutch

learning

• Flash Read Only Memory-Flash Memory

Flash memory has increased memory storage
capacity. During programming, all information
within this type of memory is erased, and then
replaced with entirely new information.

Service Programming Methods

The two methods of programming an transmission
control module (TCM) are listed below:

• Remote Programming
• Pass Thru Programming

For information on programming a TCM using one of the
methods listed above, refer to Service Programming
System (SPS) (Remote Procedure) or Service
Programming System (SPS) (Pass-Thru Procedure).

Before Programming a Control Module

Important:
DO NOT program an existing transmission control
module (TCM) with the identical software/calibration
package. This procedure is not a short cut to correct the
driveability condition. This is an ineffective repair. A
TCM should only be programmed when the following
occurs:

• When a service procedure instructs you to replace

the TCM. When the TCM from another vehicle is
installed, VIN must be changed.

• An updated software/calibrations is released.

Ensure that the following conditions are met before
programming a TCM:

• The Tech 2 PCMCIA card is programmed with the

latest software.

• The TIS 2000 is installed with the latest software.
• The hardware key is plugged into the computer

port.

• Vehicle system voltage:

– There are no charging system concerns. All

charging system concerns must be repaired
before programming the TCM.

– The battery voltage is greater than 24 volts but

less than 30 volts. The battery must be fully
charged before programming the TCM.

– A battery charger is NOT connected to the

vehicles battery. Incorrect system voltage or
voltage fluctuations from a battery charger may
cause programming failure or TCM damage.

– Turn OFF or disable any system that may put a

load on the vehicles battery. Turn OFF or
disable systems such as:

• Heating, ventilation, and air conditioning

(HVAC) systems

• Headlights
• Room  lights
• Accessory equipment

• The ignition switch is in the proper position. The

Tech 2 prompts you to turn ON the ignition, with the
engine OFF. DO NOT change the position of the
ignition switch during the programming procedure
unless instructed to do so.

• All tool connections are secure:

– The RS-232C cable
– The connection at the DLC
– The voltage supply circuits

• DO NOT disturb the tool harnesses while

programming. If an interruption occurs during the
programming procedure, programming failure or
TCM damage may occur.
If you are performing the Pass-Thru programming
procedure using a notebook computer without the
power cord, ensure that the internal battery is fully
charged.

Service Programming System (SPS) (Remote
Procedure)

The Remote Service Programming System (SPS)
method is a three-step process that involves the
following procedures:

1. Connecting the Tech 2 to the vehicle and obtaining

the information from the transmission control
module (TCM).

2. Connecting the Tech 2 to the terminal and

downloading a new calibration file from the
terminal into the Tech 2 memory.

3. Reconnecting the Tech 2 to the vehicle and

uploading the new calibration file into the TCM.

7A-202 Transmission Control System (Smoother)

Performing the Remote Procedure

1. Connect the Tech 2 to the vehicle and obtain the

transmission control module (TCM) information
using the following procedure:

Important:
Ensure the TCM is installed in the vehicle and the
battery is fully charged before programming.

1.1.Connect the Tech 2 to the vehicle data link

connector (DLC), with the engine and the Tech
2 OFF.

1.2.Turn ON the Tech 2.
1.3.Press Enter at the title screen.
1.4.Turn ON the ignition, with the engine OFF.
1.5.Select Service Programming System at the

Main Menu.

1.6.Select Request Info.
1.7.If there is already stored in the Tech 2, the

existing data is displayed on the screen. The
Tech 2 asks user to keep existing data Keep
Data or Continue to request new vehicle
information from the TCM. If there is no data in
the Tech 2, it will immediately start vehicle
identification.

1.8.Enter the vehicle description by following the

on-screen instructions based on stamped VIN
or affixed VIN plate on the vehicle.

1.9.During obtaining information, the Tech 2 is

receiving information from any modules at the
same time. But only engine control module
(ECM) information is displayed on the screen if
ECM is programmable.

1.10.Turn OFF all accessories and select

Continue.

1.11.Verify that the correct VIN is entered on the

Tech 2. If the VIN is incorrect, write down the
correct VIN.

2. Turn OFF the Tech 2.
3. Disconnect the Tech 2 from the vehicle.
4. Turn OFF the ignition.
5. Transfer the data from the terminal to the Tech 2

using the following procedure:

Important:
The TIS supports service programming with the Tech 2
scan tool only.

5.1.Connect the Tech 2 to the terminal.
5.2.Launch the TIS application at the terminal.
5.3.Select the Service Programming System at the

main screen.

5.4.Highlight the following information on the

Select Diagnostic Tool and Programming
Process screen:

• Select Diagnostic Tool-Select Tech 2.

• Select Programming Process-Identify

whether an existing TCM is being
reprogrammed or a TCM is being replaced
with a new one.

• Select TCM Location-Select Vehicle.

5.5.Select Next.
5.6.Verify the connections on the Preparing for

Communication screen and select Next.

5.7.Verify the VIN on the Validate Vehicle

Identification Number (VIN) screen and select
Next.

Important:
If the TCM is replaced to new one, VIN does not
displayed. Input correct VIN reading from stamped VIN
or affixed VIN plate on the vehicle. If the TCM from
another vehicle is installed, input correct VIN by same
way.

5.8.Highlight Engine on the System Type screen

and select Next, if requested.

5.9.Complete the following information based on

the service ID plate on the Validate Vehicle
Data screen until Next is highlighted:

• Model
• Model Year
• Engine
• System  Type
• Model Designator

5.10.Select Next.
5.11.Verify your selection on the Summary screen.

Important:
Refer to Service Bulletins before service programming
is performed if the bulletins are listed along with the
calibration files.

Important:
Select Cancel if you receive a message stating that the
calibration selected is already the current calibration in
the TCM and reprogramming with the same download is
not allowed.

5.12.Select Reprog.
5.13.The Transfer Data screen will appear until the

progress bar reaches 100%.

6. Close the application and return to the TIS

application selection screen after the download is
complete.

7. Turn OFF the Tech 2.
8. Disconnect the Tech 2 from the terminal.
9. Transfer the data from the Tech 2 to the TCM using

the following procedure:
9.1.Connect the Tech 2 to the vehicle DLC, with

the engine and the Tech 2 OFF.

9.2.Turn ON the Tech 2.
9.3.Press Enter at the Title screen.
9.4.Turn ON the ignition, with the engine OFF.