Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 235

ENGINE DRIVEABILITY AND EMISSIONS

6E–181

7

Using the DVM and check the ignition coil signal
circuit for the affected coil.
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 ignition coil module connector. 

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

for the affected coil. 

Was the problem found?

Breaker box is not available: 

1. Ignition “Off”, engine “Off”. 

2. Disconnect the ignition coil module connector and

ECM connector. 

3. Check the circuit for open or short to ground circuit

for the affected coil. 

Was the problem found?

—

Repair faulty 

harness and 

verify repair

Go to Step 8

Step

Action

Value(s)

Yes

No

18

E-18

1

Coil 1

19

E-18

3

Coil 2

E-18

E-60(J1)

18

2

Coil 1

E-18

E-60(J1)

19

3

Coil 2

6E–182

ENGINE DRIVEABILITY AND EMISSIONS

8

Using the DVM and check the ignition coil module
power supply circuit.

1.  Ignition “On”, engine “Off”. 

2. Disconnect the ignition coil module connector. 

3. Check the circuit for open circuit. 

Was the DVM indicated specified value?

Battery 
voltage

Go to Step 10

Go to Step 9

9

Repair the open or short to ground circuit between the
“IGN. Coil” fuse (15A) and ignition coil module. 
Is the action complete?

—

Verify repair

—

10

Replace the ignition coil module. 
Was the problem solved?

—

Verify repair

Go to Step 11

11

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 12

12

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

V

E-18

2

ENGINE DRIVEABILITY AND EMISSIONS

6E–183

DIAGNOSTIC TROUBLE CODE (DTC) P0443 EVAPORATIVE EMISSION (EVAP) 

CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION

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

Circuit Description

The Engine Control Module (ECM) controls the
Evaporative Emission (EVAP) Canister Purge Solenoid
Valve through the use of a control (ground) circuit. If the
ECM commands the Purge solenoid to maximum duty
cycle (100%) but the voltage remains High (12 Volts); or,
if the ECM commands the Purge solenoid to minimum
duty cycle (0%) but the voltage remains Low (0 volts),
then DTC P0443 will set.

Diagnostic Aids

• Poor connections, or a damaged harness - Inspect

the harness connectors for: backed-out terminals,
improper mating or damaged terminals. Also check
for open circuits, shorts to ground, and shorts to
voltage.

Code

Type

DTC Name

DTC Setting Condition

Fail-Safe (Back Up)

P0443

B

EVAP Emission Control System Purge 
Control Circuit

EVAP purge solenoid circuit open, short to 
ground or short to voltage circuit.

No fail-safe function.

Intake
Air
Temperature(IAT)
                    Sensor

0.5
GRN

J2-1

0.5
YEL/
GRN

J2-22

0.5
GRN/
YEL

J2-20

0.5
BLU/
YEL

0.5
BLU/
YEL

Engine
15A

Ignition
SW

Battery Voltage

J2-3

0.5
GRN/
WHT

J1-5

+5V

µP

µP

Power
Steering
Pressure
SW

Evaporativ
Emission(EVAP)
Canistor
Purge
Valve
Solenoid

Engine
Control
Module
(ECM)

6E–184

ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0443 

Evap Emission Control System Purge Control Circuit

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 By Priority” in “F0:

Diagnostic Trouble Code”. 

Is the DTC P0443 stored as “Present Failure”?

—

Go to Step 3

Refer to 

Diagnostic Aids 

and Go to Step 

3

3

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 P0443 stored in this ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids 

and Go to Step 

4

4

Check for poor/faulty connection at the purge solenoid
valve 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 purge solenoid valve.

1. Ignition “Off”,  engine “Off”. 

2. Disconnect purge solenoid valve connector. 

3. Measure the resistance of purge solenoid valve

coil. 

Does the tester indicate standard resistance? 

25 - 30

Ω at 

20°C

Go  to  Step 6

Go to Step 9

5

E-60(J1)

E-66

1

2

EVAP Purge Solenoid

1

2