Isuzu KB P190. Manual - part 585

6E–170

ENGINE DRIVEABILITY AND EMISSIONS

7

Using the DVM and check the injector power supply
circuit for the affected cylinder.

1. Ignition “On”, engine “Off”. 

2. Disconnect the injector connector for the affected

cylinder. 

3. Check the circuit for open circuit. 

Was the DVM indicated specified value?

10 - 14.5V

Go to Step 9

Go to Step 8

8

Repair the open or short to ground circuit between the
“IGN” fuse (15A) and injector for the affected cylinder. 
Is the action complete?

—

Verify repair

—

Step

Action

Value(s)

Yes

No

V

1

E-6

No.1 Cylinder

V

1

E-7

No.2 Cylinder

V

1

E-8

No.3 Cylinder

V

1

E-9

No.4 Cylinder

ENGINE DRIVEABILITY AND EMISSIONS

6E–171

9

Using the DVM and check the injector signal circuit for
the affected cylinder.
Breaker box is available: 

1. Ignition “Off”, engine “Off”. 

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

disconnected) Refer to 6E-88 page.

3. Disconnect the injector connector for the affected

cylinder. 

4. 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

J1-9

Breaker Box

2

Ω

Ω

No. 1 Cylinder

E-6

J1-22

Breaker Box

2

Ω

Ω

No. 2 Cylinder

E-7

J1-8

Breaker Box

Ω

Ω

No. 3 Cylinder

E-8

2

J1-11

Breaker Box

2

Ω

Ω

No. 4 Cylinder

E-9

6E–172

ENGINE DRIVEABILITY AND EMISSIONS

9

Breaker box is not available: 

1. Ignition “Off”, engine “Off”. 

2. Disconnect the injector connector for the affected

cylinder 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

E-60(J1)

E-6

9

2

No.1 Cylinder

E-60(J1)

E-7

22

2

No.2 Cylinder

E-60(J1)

E-8

8

2

No.3 Cylinder

E-60(J1)

E-9

11

2

No.4 Cylinder

ENGINE DRIVEABILITY AND EMISSIONS

6E–173

10

Using the DVM and check the injector signal circuit.

1. Ignition “On”, engine “Off”. 

2. Disconnect the injector connector for the affected

cylinder. 

3. Check the circuit for short to voltage circuit. 

Was the DVM indicated voltage?

—

Repair faulty 

harness and 

verify repair

Go to Step 12

11

Replace the injector for the affected cylinder. 
Was the problem solved?

—

Verify repair

Go to Step 12

12

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 13

13

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 immobilizer system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobilizer System-ECM replacement” for
the ECM/Immobilizer linking procedure.

—

Verify repair

—

Step

Action

Value(s)

Yes

No

V

2

E-6

No.1 Cylinder

V

2

E-7

No.2 Cylinder

V

2

E-8

No.3 Cylinder

V

2

E-9

No.4 Cylinder