Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 135

6E–144

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0251 (Symptom Code 9) (Flash Code 53) 

Injection Pump Malfunction

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 P0251 (Symptom Code 9) 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 P0251 (Symptom Code 9) stored in this
ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids

4

Replace the injection pump assembly. 
Is the action complete?

—

Verify repair

—

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

6E–145

Diagnostic Trouble Code (DTC) P0251 (Symptom Code A) (Flash Code 53) 

Injection Pump Malfunction

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 P0251 (Symptom Code A) 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 P0251 (Symptom Code A) stored in this
ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids

4

Replace the injection pump assembly. 
Is the action complete?

—

Verify repair

—

6E–146

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0251 (Symptom Code B) (Flash Code 53) 

Injection Pump Malfunction

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 P0251 (Symptom Code B) 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 P0251 (Symptom Code B) stored in this
ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids

4

Replace the injection pump assembly. 
Is the action complete?

—

Verify repair

—

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

6E–147

Diagnostic Trouble Code (DTC) P0251 (Symptom Code D) (Flash Code 53) 

Injection Pump Malfunction

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 P0251 (Symptom Code D) 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 P0251 (Symptom Code D) stored in this
ignition cycle?

—

Go to Step 4

Refer to 

Diagnostic Aids

4

Replace the injection pump assembly. 
Is the action complete?

—

Verify repair

—