Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 48

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

6E–187

Diagnostic Trouble Code (DTC) P0400 (Symptom Code 8) (Flash Code 32) 

Exhaust Gas Recirculation Circuit Short to Battery

Step

Action

Value(s)

Yes

No

1

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

—

Go to Step 2

Go to On Board 

Diagnostic 

(OBD) System 

Check

2

1. Connect the Tech 2. 

2. Review and record the failure information. 

3. Select “F0: Read DTC Infor As Stored By ECU” in

“F0: Diagnostic Trouble Codes”. 

Is the DTC P0400 (Symptom Code 8) stored as
“Present Failure”?

—

Go to Step 3

Refer to 

Diagnostic Aids 

and Go to Step 

3

3

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

2. Select  “F1: Clear DTC Information” in “F0:

Diagnostic Trouble Codes” with the Tech 2 and
clear the DTC information. 

3. Operate the vehicle and monitor the “F0: Read

DTC Infor As Stored By ECU” in the “F0:
Diagnostic Trouble Codes”. 

Was the DTC P0400 (Symptom Code 8) stored in this
ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids

4

Check for poor/faulty connection at the EGR EVRV or
ECM connector. If a poor/faulty connection is found,
repair as necessary. 
Was the problem found?

—

Verify repair

Go to Step 5

5

Using the DVM and check the EGR EVRV.

1. Ignition “Off”,  engine “Off”. 

2. Disconnect the EGR EVRV connector. 

3. Measure the resistance of EGR EVRV solenoid

coil. 

Does the tester indicate standard resistance?   

Approximately 

14

Ω at 20°C

Go  to  Step 6

Go to Step 8

97

1

2

C-52

C-57

1

2

EGR EVRV

1

2

6E–188

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

6

Using the DVM and check the EGR EVRV circuit. 

1. Ignition “Off”, engine “Off”. 

2. Remove the EGR EVRV connector and ECM

connector. 

3. 3. Check the circuit for short to voltage circuit. 

Was the DVM indicated specified value?

No continuity

Go to Step 10

Go to Step 7

7

Repair the short to voltage circuit. 
Is the action complete?

—

Verify repair

—

8

Substitute a known good EGR EVRV and recheck. 
Was the problem solved?

—

Go to Step 9

Go to Step 10

9

Replace the EGR EVRV. 
Is the action complete?

—

Verify repair

—

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

1

2

C-52

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

6E–189

DIAGNOSTIC TROUBLE CODE (DTC) P0500 (SYMPTOM CODE 1) 

(FLASH CODE 24) VEHICLE SPEED SENSOR CIRCUIT HIGH INPUT

DIAGNOSTIC TROUBLE CODE (DTC) P0500 (SYMPTOM CODE A) 

(FLASH CODE 24) VEHICLE SPEED SENSOR INPUT SIGNAL FREQUENCY 

TOO HIGH

DIAGNOSTIC TROUBLE CODE (DTC) P0500 (SYMPTOM CODE B) 

(FLASH CODE 24) VEHICLE SPEED SENSOR INCORRECT SIGNAL

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)

6E–190

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

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

Circuit Description

The VSS is a magnet rotated by the transmission output
shaft. The VSS uses a hall element. It interacts with the
magnetic field treated by the rotating magnet. It outputs
pulse signal. The 12 volts operating supply from the
meter fuse.
The engine control module (ECM) calculates the vehicle
speed by VSS. 

Diagnostic Aids

An intermittent may be caused by the following:

• Poor connections.

• Misrouted harness.

• Rubbed through wire insulation.

• Broken wire inside the insulation.
Check for the following conditions:

• Poor connection at ECM-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 P0500 display on the Tech2 while moving
connectors and wiring harnesses. A change in the
display will indicate the location of the fault.

Diagnostic Trouble Code (DTC) P0500 (Symptom Code 1) (Flash Code 24) 

Vehicle Speed Sensor Circuit High Input

Flash 

Code

Code

Symptom 

Code

MIL

DTC Name

DTC Setting Condition

Fail-Safe (Back Up)

24

P0500

1

ON 

at 

next 
igni-

tion 

cycle

Vehicle Speed Sensor Circuit 
High Input

Vehicle speed is more than 
200km/h.

ECM uses vehicle speed 5km/
h condition as substitute.

A

ON 

at 

next 
igni-

tion 

cycle

Vehicle Speed Sensor Input 
Signal Frequency Too High

Input signal frequency is too 
high.

ECM uses vehicle speed 5km/
h condition as substitute.

B

ON 

at 

next 
igni-

tion 

cycle

Vehicle Speed Sensor Incor-
rect Signal

1. Engine speed is more than 

3600rpm. 

2. Fuel injection quantity is 

more than 41mg/stk. 

3. Vehicle speed is below 

1.5km/h.

Fuel injection quantity is 
reduced.

Step

Action

Value(s)

Yes

No

1

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

—

Go to Step 2

Go to On Board 

Diagnostic 

(OBD) System 

Check

2

1. Connect the Tech 2. 

2. Review and record the failure information. 

3. Select “F0: Read DTC Infor As Stored By ECU” in

“F0: Diagnostic Trouble Codes”. 

Is the DTC P0500 (Symptom Code 1) stored as
“Present Failure”?

—

Go to Step 3

Refer to 

Diagnostic Aids 

and Go to Step 

3