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Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 243

ENGINE DRIVEABILITY AND EMISSIONS

6E–213

Using the DVM and check the VSS signal circuit.
Breaker box is available:

1. Ignition “Off”, engine “Off”.

2. Install the breaker box as type A. (ECM

disconnected) Ref. 6E-80.

3. Disconnect the immobiliser control unit connector.

4. Check the circuit for open or shot to ground circuit.

Was the problem found?

Breaker box is not available:

1. Ignition “Off”, engine “Off”.

2. Disconnect the immobiliser control unit connector

and ECM connector.

3. Check the circuit for open or short to ground

circuit.

Was the problem found?

—

Repair faulty

harness and

verify repair

Go to Srtep 10

Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved?

—

Verify repair

Go to Step 11

Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobiliser System-ECM replacement” for
the ECM/Immobiliser linking procedure.

—

Verify repair

—

Step

Action

Value(s)

Yes

B-68

C-56(J2)

6E–214

ENGINE DRIVEABILITY AND EMISSIONS

DIAGNOSTIC TROUBLE CODE (DTC) P1631

IMMOBILISER WRONG SIGNAL

Condition for setting the DTC and action taken when the DTC sets

Circuit Description

The ECM decides whether that is an abnomality in the
immobiliser control system. DTC P1631 is recorded by
the ECM when received response was not correct.

Diagnostic Aids

Check for the following conditions:

• Poor connection at ECM and Immobiliser-Inspect

harness connectors for backed out terminals,
improper mating, broken locks, improperly formed or

damaged terminals, and poor terminal to wire
connection.

• Damaged harness-Inspect the wiring harness for

damage, If the harness appears to be OK, disconnect
the ECM and Immobiliser, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobiliser harnass
connector while moving connectors and wiring
harnesses relates to the MIL. A change in voltage will
indicate the location of the fault.

Code

Type

DTC Name

DTC Setting Condition

Fail-Safe (Back Up)

P1631

Immobiliser Wrong Signal

Received response is not correct.

1. Engine does not start.
2. Check engine lamp flash.

Ign

Engine
Control
Module
(ECM)

Ignition
SW

µP

Meter
15A

Ign

Check
Engine

Sped

Meter

Tacho

Meter

0.85
YEL

0.8 YEL/GRN

0.5 BRN/YEL

CPU

0.5
WHT

J2-23

J2-25

0.5
BRN/
YEL

(–)

(+)

Vehicle
Speed
Sensor

J2-32

Imnobiliser
Control
Unit

ENGINE DRIVEABILITY AND EMISSIONS

6E–215

Diagnostic Trouble Code (DTC) P1631 Immobiliser Wrong Signal

Step

Action

Value(s)

Yes

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to Step 2

Go to On Board

Diagnostic

(OBD) System

Check

1. Connect the Tech 2.

2. Review and record the failure information.

3. Select “F0: Read DTC Infor By Priority” in “F0:

Diagnostic Trouble Code”.

Is the DTC P1631 stored as “Present Failure”?

—

Go to Step 3

Refer to

Diagnostic Aids

and Go to Step

1. Using the Tech2, ignition “On” and engine “Off”.

2. Select “Clear DTC Information” with the Tech2 and

clear the DTC information.

3. Operate the vehicle and monitor the “F5: Failed

This Ignition” in “F2: DTC Information”.

Was the DTC P1631 stored in this ignition cycle?

—

Go to Step 4

Refer to

Diagnostic Aids

and Go to Step

1. Using the Tech 2, ignition “On” and engine “Off”.

2. Select “Immobiliser” in the system selection menu

“Body”.

3. Select “Read DTC Info Ordered By Priority” in the

“Diagnositic Trouble Code”.

Was the any DTC's B**** stored in this ignition cycle?

—

Refer to

“Immobiliser

Workshop

Manual” & Go

to DTC Chart

B****

Go to Step 5

Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved?

—

Verify repair

Go to Step 6

—

Verify repair

—

6E–216

ENGINE DRIVEABILITY AND EMISSIONS

DIAGNOSTIC TROUBLE CODE (DTC) P1648

WRONG SECURITY CODE ENTERED

Condition for setting the DTC and action taken when the DTC sets

Circuit Description

The ECM decides whether that is an abnomality in the
immobiliser control system. DTC P1648 is recorded by
the ECM when received incorrect security code.

Diagnostic Aids

Check for the following conditions:

• Poor connection at ECM and Immobiliser-Inspect

harness connectors for backed out terminals,
improper mating, broken locks, improperly formed or

damaged terminals, and poor terminal to wire
connection.

• Damaged harness Inspect the wiring harness for

Code

Type

DTC Name

DTC Setting Condition

Fail-Safe (Back Up)

P1648

Wrong Security Code Entered

Received incorrect security code.

1. Engine does not start.
2. Check engine lamp flash.

Ign

Engine
Control
Module
(ECM)

Ignition
SW

µP

Meter
15A

Ign

Check
Engine

Sped

Meter

Tacho

Meter

0.85
YEL

0.8 YEL/GRN

0.5 BRN/YEL

CPU

0.5
WHT

J2-23

J2-25

0.5
BRN/
YEL

(–)

(+)

Vehicle
Speed
Sensor

J2-32

Imnobiliser
Control
Unit

Content .. 241 242 243 244 ..