Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 75

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

6E–295

7

Using the DVM and check the “CHECK ENGINE”
lamp circuit.
Breaker box is available: 

1. Ignition “Off”, engine “Off”. 

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

disconnected) Ref. Page 6E-81 

3. Disconnect the immobiliser control unit connector. 

4. Check the circuit for open or short to ground

circuit. 

Was the problem found?

Breaker box is not available: 

1. Ignition “Off”, engine “Off”. 

2. Disconnect the 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 Step 8

Step

Action

Value(s)

Yes

No

42

7

B-68

42

7

C-56

B-68

6E–296

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

8

Using the DVM and check the ECM and immobiliser
control unit communication circuit.

1. Ignition “Off”, engine “Off”. 

2. Disconnect the immobiliser control unit connector. 

3. Ignition “On”. 

4. Check the circuit for short to power supply circuit. 

Was the DVM indicated specified value?

Less than 1V

Go to Step 9

Repair faulty 
harness and 

verify repair

9

Using the DVM and check the ECM and immobiliser
control unit communication circuit.
Breaker box is available: 

1. Ignition “Off”, engine “Off”. 

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

disconnected) Ref. Page 6E-81 

3. Disconnect the immobiliser control unit connector. 

4. Check the circuit for open or short to ground

circuit. 

Was the problem found?

Breaker box is not available: 

1. Ignition “Off”, engine “Off”. 

2. Disconnect the 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 Step 10

Step

Action

Value(s)

Yes

No

8

V

B-68

35

8

B-68

35

8

C-56

B-68

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

6E–297

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

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

No

6E–298

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

DIAGNOSTIC TROUBLE CODE (DTC) P1613 (SYMPTOM CODE A) 

(FLASH CODE 56) IMMOBILISER NO OR WRONG SIGNAL

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

Circuit Description

The ECM decides whether that is an abnormality in the
immobiliser control system. DTC P1613 (Symptom
Code A) is recorded when received immobiliser
response signal was not correct.

Diagnostic Aids

Check for the following conditions:

• Poor connection at ECM and immobiliser control unit-

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, observe
the DTC P1613 display on the Tech2 while moving
connectors and wiring harnesses.

Flash 

Code

Code

Symptom 

Code

MIL

DTC Name

DTC Setting Condition

Fail-Safe (Back Up)

56

P1613

A

-

Immobiliser No or Wrong Sig-
nal

Received response signal is 
not correct or not received.

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

Ignition
SW

Meter
15A

6 15

7

Batt

Batt

0.5
RED/
WHT

29

0.5
ORG/
BLU

43

0.5
BRN/
YEL

42

0.5
BLK/
RED

27

0.5
BLU/
WHT

0.5 BLU/BLK

68

0.5
WHT

2.0
BLK

35

VSS

0.85
YEL

Imnobiliser

Control Unit

7

8

0.5
BRN/
YEL

IC

0.85
YEL

Glow

Check

Engine

Tacho

Meter

Speed

Meter

A/T

TCM

µP

µP

µP

µP

Engine
Control
Module
(ECM)